feat(php): use new FFI for Arboricx

The integer-arena approach (parallel global arrays) never freed nodes,
causing 6GB+ memory usage when running the self-hosted kernel. PHP
arrays don't shrink and we have no GC for them.

- Replace int-arena with plain Node objects so PHP's refcounting GC
  reclaims unreachable subtrees automatically.
- Hash-cons Stem/Fork nodes to collapse duplicate immutable subtrees.
- Cache ofNumber(0..255) to avoid re-creating byte trees.
- Eliminate indirection (tag 4) nodes entirely; projection rules now
  eagerly reduce and copy tag/a/b into the original App node.
- Remove all deref() loops — every node is exactly what it says.

Memory: 6GB+ → 24MB for `id "hello"` with runArboricxToString kernel

.gitignore

@@ -6,6 +6,8 @@
 /Dockerfile
 /config.dhall
 /result
+/result*
+.aider*
 WD
 bin/
 dist*

AGENTS.md

@@ -0,0 +1,377 @@
+# AGENTS.md - tricu Project Guide
+
+> For AI agents and contributors working in this repository.
+
+## 0. Test Driven Development
+
+Write and discuss tests with the user before working on implementation code. Do not modify existing tests without explicit permission.
+
+## 1. Build & Test
+
+```bash
+# Haskell tests (default check)
+nix flake check
+
+# Zig build
+nix build .#tricu-zig
+
+# Zig tests (separate target — not part of nix flake check)
+nix build .#tricu-zig-tests
+
+# Full build
+nix build .#
+```
+
+### ⚠️ Never call `cabal` directly
+
+> **Rule of thumb:** if it builds, links, or tests, it goes through `nix`.
+
+## 2. Project Overview
+
+**tricu** (pronounced "tree-shoe") is a programming-language experiment written in Haskell. It implements [Triage Calculus](https://olydis.medium.com/a-visual-introduction-to-tree-calculus-2f4a34ceffc2), an extension of Barry Jay's Tree Calculus, with lambda-abstraction sugar that gets eliminated back to pure tree calculus terms.
+
+### Core types (in `src/Research.hs`)
+
+| Type | Description |
+|------|-------------|
+| `T = Leaf \| Stem T \| Fork T T` | Tree Calculus term (the runtime value) |
+| `TricuAST` | Parsed AST with `SDef`, `SApp`, `SLambda`, etc. |
+| `LToken` | Lexer tokens |
+| `Node` / `MerkleHash` | Content-addressed Merkle DAG nodes |
+
+### Source modules (Haskell)
+
+| Module | Purpose |
+|--------|---------|
+| `Main.hs` | CLI entry point (`cmdargs`), three modes: `repl`, `eval`, `decode` |
+| `Eval.hs` | Interpreter: `evalTricu`, `result`, `evalSingle` |
+| `Parser.hs` | Megaparsec parser → `TricuAST` |
+| `Lexer.hs` | Megaparsec lexer → `LToken` |
+| `FileEval.hs` | File loading, module imports, `!import` |
+| `REPL.hs` | Interactive Read-Eval-Print Loop (haskeline) |
+| `Research.hs` | Core types, `apply` reduction, booleans, marshalling (`ofString`, `ofNumber`), output formatters (`toAscii`, `toTernaryString`, `decodeResult`) |
+| `ContentStore.hs` | SQLite-backed term persistence |
+| `Wire.hs` | Arboricx portable wire format — encode/decode/import/export of Merkle-DAG bundle blobs |
+
+### Multi-language Arboricx ecosystem
+
+Arboricx is the portable executable-object format used by tricu. The project now includes native parsing and execution in multiple languages:
+
+| Language | Location | Capabilities |
+|----------|----------|--------------|
+| **Haskell** | `src/Wire.hs`, `src/Research.hs` | Reference implementation — bundle encode/decode, content store, full Tree Calculus reduction |
+| **tricu (self-hosted)** | `kernel_run_arboricx_typed.dag` | A self-hosting Arboricx parser/executor written in tricu itself. Used as a kernel inside the Zig host for maximum portability ("cool but useless" — ~3s for `append`) |
+| **Zig** | `ext/zig/` | **Production host** — native bundle parser, WHNF reducer, C ABI (`libarboricx.so` / `.a`), CLI (`tricu-zig`), Python FFI support |
+| **JavaScript (Node)** | `ext/js/` | Native bundle parser, manifest decoder, Merkle DAG verifier, Tree Calculus reducer, CLI runner |
+| **PHP** | `ext/php/` | FFI wrapper around `libarboricx.so`, CLI runner |
+
+All hosts share the same bundle format and Merkle hashing scheme.
+
+### File extensions
+
+- `.hs` - Haskell source
+- `.tri` - tricu language source (used in `lib/`, `test/`, `demos/`)
+- `.arboricx` - Portable executable bundle
+- `.dag` - Serialized kernel DAG (used by `gen_kernel.zig` at build time)
+
+## 3. Test Suite
+
+### Haskell tests
+
+Tests live in `test/Spec.hs` and use **Tasty** + **HUnit**.
+
+```bash
+nix flake check
+```
+
+### Test groups
+
+| Group | What it covers |
+|-------|----------------|
+| `lexer` | Megaparsec lexer - identifiers, keywords, strings, escapes, invalid tokens |
+| `parser` | Parser - defs, lambda, applications, lists, comments, parentheses |
+| `simpleEvaluation` | Core `apply` reduction rules, variable substitution, immutability |
+| `lambdas` | Lambda elimination, SKI calculus, higher-order functions, currying, shadowing, free vars |
+| `providedLibraries` | `lib/list.tri` - triage, booleans, list ops (`head`, `tail`, `map`, `emptyList?`, `append`, `equal?`) |
+| `fileEval` | Loading `.tri` files, multi-file context, decode |
+| `modules` | `!import`, cyclic deps, namespacing, multi-level imports, unresolved vars, local namespaces |
+| `demos` | `demos/*.tri` - structural equality, `toSource`, `size`, level-order traversal |
+| `decoding` | `decodeResult` - Leaf, numbers, strings, lists, mixed |
+| `elimLambdaSingle` | Lambda elimination: eta reduction, SDef binding, semantics preservation |
+| `stressElimLambda` | Lambda elimination stress test: 200 vars, 800-body curried lambda |
+
+### Zig tests
+
+Run separately via:
+
+```bash
+nix build .#tricu-zig-tests
+```
+
+These are **not** included in `nix flake check`. The test derivation compiles and runs:
+
+| Test | What it covers |
+|------|----------------|
+| `c_abi_test.c` | Smoke tests — leaf, stem, fork, app, reduce, number/string roundtrip, kernel root |
+| `c_abi_append_test.c` | Kernel path — `append.arboricx` with string arguments via Tricu kernel |
+| `native_bundle_append_test.c` | Native fast path — `append.arboricx` loaded natively, applied, reduced |
+| `native_bundle_id_test.c` | Native fast path — `id.arboricx` |
+| `native_bundle_bools_test.c` | Native fast path — `true.arboricx` / `false.arboricx` |
+| `python_ffi_test.py` | Python ctypes FFI — tests both kernel and native paths for `id` and `append` |
+
+## 4. tricu Language Quick Reference
+
+```
+t                      → Leaf (the base term)
+t t                    → Stem Leaf
+t t t                  → Fork Leaf Leaf
+
+x = t                  → Define term x = Leaf
+id = (a : a)           → Lambda identity (eliminates to tree calculus)
+head (map f xs)        → From lib/list.tri
+
+!import "./path.tri" NS  → Import file under namespace
+
+-- line comment
+```
+
+CRITICAL:
+
+When working with recursion in `tricu` files:
+
+1. Put consumed data first in recursive workers.
+2. Let data shape drive recursion.
+3. Do not let counters unroll over abstract input.
+
+## 5. Output Formats
+
+The `eval` command accepts `--form` (shorthand `-t`):
+
+| Format | Value | Description |
+|--------|-------|-------------|
+| `tree` | `TreeCalculus` | Simple `t` form (default) |
+| `fsl` | `FSL` | Full show representation |
+| `ast` | `AST` | Parsed AST representation |
+| `ternary` | `Ternary` | Ternary string encoding |
+| `ascii` | `Ascii` | ASCII-art tree diagram |
+| `decode` | `Decode` | Human-readable (strings, numbers, lists) |
+
+## 6. Content Addressing
+
+Each `T` term is content-addressed via a Merkle DAG:
+
+```
+NLeaf       → 0x00
+NStem(h)    → 0x01 || h (32 bytes)
+NFork(l,r)  → 0x02 || l (32 bytes) || r (32 bytes)
+
+hash = SHA256("arboricx.merkle.node.v1" <> 0x00 <> serialized_node)
+```
+
+This is stored in SQLite via `ContentStore.hs`. Hash suffixes on identifiers (e.g., `foo_abc123...`) are validated: 16–64 hex characters (SHA256).
+
+## 7. Arboricx Portable Bundles (`.arboricx`)
+
+Portable executable bundles are generated via `Wire.hs`. See `docs/arboricx-bundle-format.md` for the full binary format spec.
+
+```bash
+# Export a bundle from the content store
+./result/bin/tricu export -o myterm.arboricx myterm
+
+# Run a bundle (requires TRICU_DB_PATH)
+./result/bin/tricu import -f lib/list.tri
+TRICU_DB_PATH=/tmp/tricu.db ./result/bin/tricu export -o list_ops.arboricx append
+```
+
+## 8. Zig Arboricx Host (`ext/zig/`)
+
+The Zig host is a fast implementation for running Arboricx bundles. It provides a native bundle parser and arena-based evaluator.
+
+### Modules
+
+| File | Role |
+|------|------|
+| `src/main.zig` | CLI entrypoint — default native path, `--kernel` fallback |
+| `src/bundle.zig` | Native Arboricx bundle parser — verifies digests, hashes, loads DAG into arena |
+| `src/c_abi.zig` | C FFI exports — `arboricx_init`, tree constructors, codecs, reduction, bundle loading |
+| `src/reduce.zig` | WHNF reducer (Tree Calculus `apply` rules) |
+| `src/arena.zig` | Node arena (`ArrayListUnmanaged`) |
+| `src/tree.zig` | `Node` union + iterative `copyTree` |
+| `src/codecs.zig` | Number/string/list/bytes encoding + result unwrapping |
+| `src/kernel.zig` | Embeds DAG kernel into arena (fallback path only) |
+| `src/ternary.zig` | Ternary string parser for Tree Calculus terms |
+| `tools/gen_kernel.zig` | Build-time tool: converts `.dag` → `kernel_embed.zig` |
+| `include/arboricx.h` | C header for `libarboricx` |
+
+### C ABI
+
+Key functions:
+
+```c
+arb_ctx_t* arboricx_init(void);
+uint32_t arb_load_bundle(arb_ctx_t*, const uint8_t* bytes, size_t len, const char* name);
+uint32_t arb_load_bundle_default(arb_ctx_t*, const uint8_t* bytes, size_t len);
+uint32_t arb_reduce(arb_ctx_t*, uint32_t root, uint64_t fuel);
+```
+
+`arb_reduce` evaluates in a **fresh scratch arena** so garbage never accumulates.
+
+### Stack size requirement
+
+Tree Calculus reduction is deeply recursive. Assume a segfault is a memory limitation until proven otherwise.
+
+```bash
+ulimit -s 32768   # 32 MB
+```
+
+### Performance comparison
+
+| Fixture | Native path | Kernel path (`--kernel`) |
+|---------|-------------|--------------------------|
+| `append "hello " "world"` | **~0.007 s** | ~3.4 s |
+| `id "hello"` | **~0.005 s** | ~0.38 s |
+
+The kernel path is kept as a "cool but useless" fallback — the DAG is tiny (~30 KB) so the cost is negligible.
+
+## 9. Nix Flake Outputs
+
+| Output | Description |
+|--------|-------------|
+| `packages.default` / `packages.tricu` | Haskell tricu package |
+| `packages.tricu-zig` | Zig CLI + `libarboricx.a` + `libarboricx.so` + `arboricx.h` |
+| `packages.tricu-zig-tests` | **Separate test target** — C ABI + native bundle + Python FFI tests |
+| `packages.tricu-php` | PHP source + `libarboricx.so` + `tricu-php` wrapper script |
+| `packages.tricu-php-tests` | **Separate test target** — PHP FFI tests against fixture bundles |
+| `packages.tricu-container` | Docker image |
+| `checks.default` / `checks.tricu` | Haskell test suite via Tasty/HUnit |
+
+`tricu-zig-tests` is deliberately **not** in `checks` so `nix flake check` remains fast.
+
+## 10. Directory Layout
+
+```
+tricu/
+├── flake.nix           # Nix flake: packages, tests, devShell
+├── tricu.cabal         # Cabal package (used via callCabal2nix)
+├── AGENTS.md           # This file
+├── src/                # Haskell modules
+│   ├── Main.hs
+│   ├── Eval.hs
+│   ├── Parser.hs
+│   ├── Lexer.hs
+│   ├── FileEval.hs
+│   ├── REPL.hs
+│   ├── Research.hs
+│   ├── ContentStore.hs
+│   └── Wire.hs
+├── test/
+│   ├── Spec.hs         # Tasty + HUnit tests
+│   ├── *.tri           # tricu test programs
+│   ├── *.arboricx      # Arboricx bundle fixtures
+│   └── local-ns/       # Module namespace test files
+├── lib/
+│   ├── base.tri
+│   ├── list.tri
+│   └── patterns.tri
+├── demos/
+│   ├── equality.tri
+│   ├── size.tri
+│   ├── toSource.tri
+│   ├── levelOrderTraversal.tri
+│   └── patternMatching.tri
+├── ext/                # Multi-language Arboricx hosts
+│   ├── js/             # Node.js bundle parser + reducer
+│   │   ├── src/
+│   │   │   ├── bundle.js
+│   │   │   ├── manifest.js
+│   │   │   ├── merkle.js
+│   │   │   ├── tree.js
+│   │   │   ├── codecs.js
+│   │   │   └── cli.js
+│   │   └── test/
+│   ├── php/            # PHP FFI host for libarboricx.so
+│   │   ├── src/
+│   │   │   └── ffi.php
+│   │   └── run.php
+│   └── zig/            # Zig production host
+│       ├── build.zig
+│       ├── build.zig.zon
+│       ├── kernel_run_arboricx_typed.dag
+│       ├── include/arboricx.h
+│       ├── src/
+│       │   ├── main.zig
+│       │   ├── bundle.zig
+│       │   ├── c_abi.zig
+│       │   ├── codecs.zig
+│       │   ├── kernel.zig
+│       │   ├── reduce.zig
+│       │   ├── arena.zig
+│       │   ├── tree.zig
+│       │   └── ternary.zig
+│       ├── tests/
+│       │   ├── c_abi_test.c
+│       │   ├── c_abi_append_test.c
+│       │   ├── native_bundle_append_test.c
+│       │   ├── native_bundle_id_test.c
+│       │   ├── native_bundle_bools_test.c
+│       │   └── python_ffi_test.py
+│       └── tools/
+│           └── gen_kernel.zig
+└── docs/
+    └── arboricx-bundle-format.md
+```
+
+## 11. Content Store Workflow (Custom DB)
+
+The content store location is controlled by the `TRICU_DB_PATH` environment variable. When set, `eval` mode automatically loads all stored terms into the initial environment, so you can call any previously imported/evaluated term by name.
+
+```bash
+# Use a local DB
+export TRICU_DB_PATH=/tmp/tricu-local.db
+
+# Import terms from the standard library
+./result/bin/tricu import -f lib/list.tri
+
+# Now use them in eval mode
+echo "not? (t t)" | ./result/bin/tricu eval -t decode
+# Output: t
+
+echo "not? (t t t)" | ./result/bin/tricu eval -t decode
+# Output: Stem Leaf
+
+echo "equal? (t t) (t t t)" | ./result/bin/tricu eval -t decode
+# Output: t
+
+# Check what's in the store
+./result/bin/tricu
+t> !definitions
+```
+
+Without `TRICU_DB_PATH` set, `eval` uses only the terms defined in the input file(s).
+
+## 12. Development Tips
+
+- **REPL:** `nix run .#` starts the interactive tricu REPL.
+- **Evaluate files:** `nix run .# -- eval -f demos/equality.tri`
+- **Zig host:** `nix build .#tricu-zig` then `./result/bin/tricu-zig <bundle> [args...]`
+- **Zig tests:** `nix build .#tricu-zig-tests`
+- **GHC options:** `-threaded -rtsopts -with-rtsopts=-N` for parallel runtime. Use `-N` RTS flag for multi-core.
+- **Upx** is in the devShell for binary compression if needed.
+
+## 13. Viewing Haskell Dependency Docs from Nix
+
+When you need Haddock documentation for a Haskell dependency available in Nixpkgs, build the package's `doc` output directly with `^doc`.
+
+Example:
+
+Replace `megaparsec` with the dependency name you need:
+
+```sh
+nix build "nixpkgs#haskellPackages.${pkg}^doc"
+```
+
+View the available documentation files:
+
+```sh
+find ./result-doc -type f \( -name '*.html' -o -name '*.haddock' \) | sort
+```

README.md

@@ -2,37 +2,31 @@
 
 ## Introduction
 
-tricu (pronounced "tree-shoe") is a purely functional interpreted language implemented in Haskell. It is fundamentally based on the application of [Tree Calculus](https://github.com/barry-jay-personal/typed_tree_calculus/blob/main/typed_program_analysis.pdf) terms, but minimal syntax sugar is included to provide a useful programming tool. 
-
-*tricu is under active development and you should expect breaking changes with every commit.*
+tricu (pronounced "tree-shoe") is a programming language experiment in Haskell. It is fundamentally based on the application of [Triage Calculus](https://olydis.medium.com/a-visual-introduction-to-tree-calculus-2f4a34ceffc2), an extended form of [Tree Calculus](https://github.com/barry-jay-personal/typed_tree_calculus/blob/main/typed_program_analysis.pdf), but minimal syntax sugar is included.
 
 tricu is the word for "tree" in Lojban: `(x1) is a tree of species/cultivar (x2)`.
 
-## Features
+I have fully embraced the slopmachine (LLM-assisted development) for this project. Nothing is stable or sacred. We will discover sanity at the end of the journey but we won't strive for it until then.
 
-- Tree Calculus operator: `t`
-- Assignments: `x = t t`
-- Immutable definitions
-- Lambda abstraction syntax: `id = (\a : a)`
-- List, Number, and String literals: `[(2) ("Hello")]` 
-- Function application: `not (not false)`
-- Higher order/first-class functions: `map (\a : append a "!") [("Hello")]`
-- Intensionality blurs the distinction between functions and data (see REPL examples)
-- Simple module system for code organization
+This README.md is human written. No other .md file will be until stabilization.
+
+## Acknowledgements 
+
+Tree Calculus was discovered by [Barry Jay](https://github.com/barry-jay-personal/blog). The addition of Triage rules were suggested by [Johannes Bader](https://johannes-bader.com/). Johannes is also the creator of [treecalcul.us](https://treecalcul.us) which has a great intuitive code playground using his language LambAda.
 
 ## REPL examples
 
 ```
 tricu < -- Anything after `--` on a single line is a comment
-tricu < id = (\a : a) -- Lambda abstraction is eliminated to tree calculus terms
-tricu < head (map (\i : append i " world!") [("Hello, ")])
+tricu < id = (a : a) -- Lambda abstraction is eliminated to tree calculus terms
+tricu < head (map (i : append i " world!") [("Hello, ")])
 tricu > "Hello,  world!"
-tricu < id (head (map (\i : append i " world!") [("Hello, ")]))
+tricu < id (head (map (i : append i " world!") [("Hello, ")]))
 tricu > "Hello,  world!"
 
 tricu < -- Intensionality! We can inspect the structure of a function or data.
-tricu < triage = (\a b c : t (t a b) c)
-tricu < test = triage "Leaf" (\z : "Stem") (\a b : "Fork")
+tricu < triage = (a b c : t (t a b) c)
+tricu < test = triage "Leaf" (z : "Stem") (a b : "Fork")
 tricu < test (t t)
 tricu > "Stem"
 tricu < -- We can even convert a term back to source code (/demos/toSource.tri)
@@ -41,13 +35,27 @@ tricu > "(t (t (t t) (t t t)) (t t (t t t)))"
 tricu < -- or calculate its size (/demos/size.tri)
 tricu < size not?
 tricu > 12
+
+tricu < !help 
+tricu version 1.1.0
+Available commands:
+    !exit        - Exit the REPL
+    !clear       - Clear the screen
+    !reset       - Reset preferences for selected versions
+    !help        - Show tricu version and available commands
+    !output      - Change output format (tree|fsl|ast|ternary|ascii|decode)
+    !definitions - List all defined terms in the content store
+    !import      - Import definitions from file to the content store
+    !watch       - Watch a file for changes, evaluate terms, and store them
+    !refresh     - Refresh environment from content store (definitions are live)
+    !versions    - Show all versions of a term by name
+    !select      - Select a specific version of a term for subsequent lookups
+    !tag         - Add or update a tag for a term by hash or name
 ```
 
 ## Installation and Use
 
-[Releases are available for Linux.](https://git.eversole.co/James/tricu/releases)
-
-Or you can easily build and run this project using [Nix](https://nixos.org/download/).
+You can easily build and run this project using [Nix](https://nixos.org/download/).
 
 - Quick Start (REPL): 
   - `nix run git+https://git.eversole.co/James/tricu`
@@ -56,36 +64,6 @@ Or you can easily build and run this project using [Nix](https://nixos.org/downl
 
 `./result/bin/tricu --help`
 
-```
-tricu Evaluator and REPL
+## Usage
 
-tricu [COMMAND] ... [OPTIONS]
-  tricu: Exploring Tree Calculus
-
-Common flags:
-  -? --help       Display help message
-  -V --version    Print version information
-
-tricu [repl] [OPTIONS]
-  Start interactive REPL
-
-tricu eval [OPTIONS]
-  Evaluate tricu and return the result of the final expression.
-
-  -f --file=FILE  Input file path(s) for evaluation.
-                    Defaults to stdin.
-  -t --form=FORM  Optional output form: (tree|fsl|ast|ternary|ascii|decode).
-                    Defaults to tricu-compatible `t` tree form.
-
-tricu decode [OPTIONS]
-  Decode a Tree Calculus value into a string representation.
-
-  -f --file=FILE  Optional input file path to attempt decoding.
-                    Defaults to stdin.
-```
-
-## Acknowledgements 
-
-Tree Calculus was discovered by [Barry Jay](https://github.com/barry-jay-personal/blog). 
-
-[treecalcul.us](https://treecalcul.us) is an excellent website with an intuitive Tree Calculus code playground created by [Johannes Bader](https://johannes-bader.com/) that introduced me to Tree Calculus.
+I'll update this once the CLI stabilizes more.

demos/equality.tri

@@ -11,20 +11,17 @@ demo_true  = t t
 not_TC?     = t (t (t t) (t t t)) (t t (t t t))
 
 -- /demos/toSource.tri contains an explanation of `triage`
-demo_triage = \a b c : t (t a b) c
-demo_matchBool = (\ot of : demo_triage
-  of
-  (\_ : ot)
-  (\_ _ : ot)
-)
+demo_triage = a b c : t (t a b) c
+demo_matchBool = a b : demo_triage b (_ : a) (_ _ : a)
+
 -- Lambda representation of the Boolean `not` function
 not_Lambda? = demo_matchBool demo_false demo_true
 
--- Since tricu eliminates Lambda terms to SKI combinators, the tree form of many
+-- As tricu eliminates Lambda terms to SKI combinators, the tree form of many
 -- functions defined via Lambda terms are larger than the most efficient TC
--- representation. Between different languages that evaluate to tree calculus 
--- terms, the exact implementation of Lambda elimination may differ and lead 
--- to different tree representations even if they share extensional behavior.
+-- representation possible. Between different languages that evaluate to tree
+-- calculus terms, the exact implementation of Lambda elimination may differ
+-- and lead to different trees even if they share extensional behavior.
 
 -- Let's see if these are the same:
 lambdaEqualsTC = equal? not_TC? not_Lambda?

demos/levelOrderTraversal.tri

@@ -18,47 +18,47 @@ main = exampleTwo
 --    /   /  \
 --   4   5    6
 
-label = \node : head node
+label = node : head node
 
-left = (\node : if (emptyList? node)
-  [] 
-  (if (emptyList? (tail node)) 
-    [] 
+left = node : (if (emptyList? node)
+  []
+  (if (emptyList? (tail node))
+    []
     (head (tail node))))
 
-right = (\node : if (emptyList? node) 
-  [] 
-  (if (emptyList? (tail node)) 
-    [] 
-    (if (emptyList? (tail (tail node))) 
-      [] 
+right = node : (if (emptyList? node)
+  []
+  (if (emptyList? (tail node))
+    []
+    (if (emptyList? (tail (tail node)))
+      []
       (head (tail (tail node))))))
 
-processLevel = y (\self queue : if (emptyList? queue) 
-  [] 
-  (pair (map label queue) (self (filter 
-    (\node : not? (emptyList? node)) 
+processLevel = y (self queue : if (emptyList? queue)
+  []
+  (pair (map label queue) (self (filter
+    (node : not? (emptyList? node))
       (append (map left queue) (map right queue))))))
 
-levelOrderTraversal_ = \a : processLevel (t a t)
+levelOrderTraversal_ = a : processLevel (t a t)
 
-toLineString = y (\self levels : if (emptyList? levels) 
-  "" 
-  (append 
-    (append (map (\x : append x " ") (head levels)) "") 
+toLineString = y (self levels : if (emptyList? levels)
+  ""
+  (append
+    (append (map (x : append x " ") (head levels)) "")
     (if (emptyList? (tail levels)) "" (append (t (t 10 t) t) (self (tail levels))))))
 
-levelOrderToString = \s : toLineString (levelOrderTraversal_ s)
+levelOrderToString = s : toLineString (levelOrderTraversal_ s)
 
-flatten = foldl (\acc x : append acc x) ""
+flatten = foldl (acc x : append acc x) ""
 
-levelOrderTraversal = \s : append (t 10 t) (flatten (levelOrderToString s))
+levelOrderTraversal = s : append (t 10 t) (flatten (levelOrderToString s))
 
-exampleOne = levelOrderTraversal [("1") 
-                                 [("2") [("4") t t] t] 
+exampleOne = levelOrderTraversal [("1")
+                                 [("2") [("4") t t] t]
                                  [("3") [("5") t t] [("6") t t]]]
 
-exampleTwo = levelOrderTraversal [("1") 
-                                 [("2") [("4") [("8") t t] [("9") t t]] 
-                                        [("6") [("10") t t] [("12") t t]]] 
+exampleTwo = levelOrderTraversal [("1")
+                                 [("2") [("4") [("8") t t] [("9") t t]]
+                                        [("6") [("10") t t] [("12") t t]]]
                                  [("3") [("5") [("11") t t] t] [("7") t t]]]

demos/patternMatching.tri

@@ -0,0 +1,37 @@
+!import "../lib/patterns.tri" !Local
+
+-- We can do conditional pattern matching by providing a list of lists, where
+-- each sublist contains a boolean expression and a function to return if said
+-- boolean expression evaluates to true.
+
+value = 42
+main  = match value [[(equal? "Hello") (_ : ", world!")] [(equal? 42) (_ : "The answer.")]]
+
+-- < main
+-- > "The answer."
+
+matchExample = (x : match x
+  [[(equal? 1)  (_ : "one")]
+   [(equal? 2)  (_ : "two")]
+   [(equal? 3)  (_ : "three")]
+   [(equal? 4)  (_ : "four")]
+   [(equal? 5)  (_ : "five")]
+   [(equal? 6)  (_ : "six")]
+   [(equal? 7)  (_ : "seven")]
+   [(equal? 8)  (_ : "eight")]
+   [(equal? 9)  (_ : "nine")]
+   [(equal? 10) (_ : "ten")]
+   [ otherwise  (_ : "I ran out of fingers!")]])
+
+-- < matchExample 3
+-- > "three"
+-- < matchExample 5
+-- > "five"
+-- < matchExample 9
+-- > "nine"
+-- < matchExample 11
+-- > "I ran out of fingers!"
+-- < matchExample "three"
+-- > "I ran out of fingers!"
+-- < matchExample [("hello") ("world")]
+-- > "I ran out of fingers!"

demos/size.tri

@@ -3,11 +3,9 @@
 
 main = size size
 
-size = (\x :
-  (y (\self x :
-    compose succ
-      (triage
-        (\x : x)
-        self
-        (\x y : compose (self x) (self y))
-        x)) x 0))
+size = x : y (self x : compose succ (triage
+  id
+  self
+  (x y : compose (self x) (self y))
+  x)
+) x 0

demos/toSource.tri

@@ -18,25 +18,25 @@ main = toSource not?
 sourceLeaf = t (head "t")
 
 -- Stem case
-sourceStem = (\convert : (\a rest :
+sourceStem = convert : (a rest :
   t (head "(")                       -- Start with a left parenthesis "(".
     (t (head "t")                    -- Add a "t"
       (t (head " ")                  -- Add a space.
         (convert a                   -- Recursively convert the argument.
-          (t (head ")") rest))))))   -- Close with ")" and append the rest.
+          (t (head ")") rest)))))   -- Close with ")" and append the rest.
 
 -- Fork case
-sourceFork = (\convert : (\a b rest :
+sourceFork = convert : (a b rest :
   t (head "(")                           -- Start with a left parenthesis "(".
     (t (head "t")                        -- Add a "t"
       (t (head " ")                      -- Add a space.
         (convert a                       -- Recursively convert the first arg.
           (t (head " ")                  -- Add another space.
             (convert b                   -- Recursively convert the second arg.
-              (t (head ")") rest)))))))) -- Close with ")" and append the rest.
+              (t (head ")") rest))))))) -- Close with ")" and append the rest.
 
 -- Wrapper around triage 
-toSource_ = y (\self arg :
+toSource_ = y (self arg :
   triage
     sourceLeaf        -- `triage` "a" case, Leaf
     (sourceStem self) -- `triage` "b" case, Stem
@@ -44,7 +44,7 @@ toSource_ = y (\self arg :
     arg)              -- The term to be inspected
 
 -- toSource takes a single TC term and returns a String
-toSource = \v : toSource_ v ""
+toSource = v : toSource_ v ""
 
 exampleOne = toSource true -- OUT: "(t t)"
 exampleTwo = toSource not? -- OUT: "(t (t (t t) (t t t)) (t t (t t t)))"

docs/arboricx-bundle-format.md

@@ -0,0 +1,419 @@
+# Arboricx Portable Bundle Format Specification
+
+**Version:** 0.1
+**Status:** Exploratory
+**Author:** A range of slopmachines guided by James Eversole
+**Human Review Status:** 5 minute scan-through - this is an evolving and malleable document
+
+The Arboricx Portable Bundle is a self-contained, content-addressed binary format for distributing Tree Calculus programs and their associated Merkle DAGs. It provides:
+
+- A fixed binary container with header, section directory, and typed sections
+- A language-neutral Merkle node layer for content-addressed tree values
+- A fixed-order binary manifest for semantic metadata, exports, and optional extensions
+
+## Table of Contents
+
+1. [Top-Level Container Layout](#1-top-level-container-layout)
+2. [Header](#2-header)
+3. [Section Directory](#3-section-directory)
+4. [Section: Manifest (type 1)](#4-section-manifest-type-1)
+5. [Section: Nodes (type 2)](#5-section-nodes-type-2)
+6. [Merkle Node Payload Format](#6-merkle-node-payload-format)
+7. [Merkle Hash Computation](#7-merkle-hash-computation)
+8. [Tree Calculus Reduction Semantics](#8-tree-calculus-reduction-semantics)
+9. [Binary Primitives](#9-binary-primitives)
+10. [Bundle Verification](#10-bundle-verification)
+11. [Known Section Types](#11-known-section-types)
+
+---
+
+## 1. Top-Level Container Layout
+
+An Arboricx bundle is a flat binary blob with the following layout:
+
+```
++------------------+------------------+------------------+------------------+
+| Header           | Section Directory| Manifest Section | Nodes Section    |
+| (32 bytes)       | (N × 60 bytes)   | (variable)       | (variable)       |
++------------------+------------------+------------------+------------------+
+```
+
+The container uses **big-endian** byte order for all multi-byte integers.
+
+Total bundle size = 32 + (sectionCount × 60) + manifestSize + nodesSize
+
+---
+
+## 2. Header
+
+| Offset | Size | Field | Description |
+|--------|------|-------|-------------|
+| 0 | 8 bytes | Magic | ASCII `"ARBORICX"` (`0x41 0x52 0x42 0x4F 0x52 0x49 0x43 0x58`) |
+| 8 | 2 bytes | Major version | `u16` BE. Currently `1` |
+| 10 | 2 bytes | Minor version | `u16` BE. Currently `0` |
+| 12 | 4 bytes | Section count | `u32` BE. Number of entries in the section directory |
+| 16 | 8 bytes | Flags | `u64` BE. Reserved; currently all zeros |
+| 24 | 8 bytes | Directory offset | `u64` BE. Byte offset from the start of the bundle to the section directory |
+
+**Constraints:**
+- Major version must be `1`. Bundles with unsupported major versions are rejected.
+- The directory offset must point to a valid location within the bundle.
+- The directory offset is always `32` for bundles with the current layout (header immediately followed by the directory).
+
+---
+
+## 3. Section Directory
+
+The section directory is an array of `N` entries, where `N` is the section count from the header. Each entry is exactly **60 bytes**.
+
+| Offset (within entry) | Size | Field | Description |
+|----------------------|------|-------|-------------|
+| 0 | 4 bytes | Type | `u32` BE. Section type identifier (see [Known Section Types](#11-known-section-types)) |
+| 4 | 2 bytes | Version | `u16` BE. Section-specific version |
+| 6 | 2 bytes | Flags | `u16` BE. Bit flags: bit 0 (`0x0001`) = critical section |
+| 8 | 2 bytes | Compression | `u16` BE. Compression codec (currently only `0` = none) |
+| 10 | 2 bytes | Digest algorithm | `u16` BE. Hash algorithm (currently only `1` = SHA-256) |
+| 12 | 8 bytes | Offset | `u64` BE. Byte offset from the start of the bundle to the section data |
+| 20 | 8 bytes | Length | `u64` BE. Length of the section data in bytes |
+| 28 | 32 bytes | SHA-256 digest | Raw digest of the section data |
+
+**Verification:**
+- Unknown critical sections (flags & `0x0001`) are rejected.
+- Compression must be `0` (none).
+- Digest algorithm must be `1` (SHA-256).
+- The SHA-256 digest in the directory entry must match `SHA256(section_data)`.
+
+---
+
+## 4. Section: Manifest (type 1)
+
+The manifest is a binary encoding of bundle metadata. It uses a **fixed-order core** layout followed by an optional **TLV tail** for extensibility.
+
+### 4.1 Format
+
+```
+Manifest =
+  magic            8 bytes    "ARBMNFST"
+  major            u16 BE     Manifest major version (1)
+  minor            u16 BE     Manifest minor version (0)
+
+  schema           string     Length-prefixed UTF-8 text
+  bundleType       string     Length-prefixed UTF-8 text
+
+  treeCalculus     string     Length-prefixed UTF-8 text
+  treeHashAlgorithm string    Length-prefixed UTF-8 text
+  treeHashDomain   string     Length-prefixed UTF-8 text
+  treeNodePayload  string     Length-prefixed UTF-8 text
+
+  runtimeSemantics string     Length-prefixed UTF-8 text
+  runtimeEvaluation string    Length-prefixed UTF-8 text
+  runtimeAbi       string     Length-prefixed UTF-8 text
+  capabilityCount  u32 BE     Number of capability strings
+  capabilities     string[]   Array of length-prefixed UTF-8 capability strings
+
+  closure          u8         0 = complete, 1 = partial
+  rootCount        u32 BE     Number of root entries
+  roots            Root[]     Array of root entries
+  exportCount      u32 BE     Number of export entries
+  exports          Export[]   Array of export entries
+
+  metadataFieldCount u32 BE   Number of metadata TLV entries
+  metadataFields   TLV[]      Metadata tag-value entries
+  extensionFieldCount u32 BE  Number of extension TLV entries
+  extensionFields  TLV[]      Extension tag-value entries (skipped by parsers)
+```
+
+**Trailing bytes after the manifest must be zero** (no leftover data).
+
+### 4.2 String Format
+
+Every `string` field uses the same encoding:
+
+```
+string =
+  length      u32 BE    Number of UTF-8 bytes in the string (not the number of characters)
+  bytes       byte[length]  UTF-8 encoded string content
+```
+
+The length field carries the byte count, so parsers can skip strings without decoding UTF-8.
+
+### 4.3 Root Entry
+
+```
+Root =
+  hash        32 bytes    Raw SHA-256 hash of the Merkle node
+  role        string      Length-prefixed UTF-8 text ("default" for the first root, "root" for others)
+```
+
+The hash is stored as **raw bytes** (not hex-encoded). It corresponds to the Merkle hash of the node.
+
+### 4.4 Export Entry
+
+```
+Export =
+  name        string      Length-prefixed UTF-8 text (export identifier)
+  root        32 bytes    Raw SHA-256 hash of the Merkle node
+  kind        string      Length-prefixed UTF-8 text (currently "term")
+  abi         string      Length-prefixed UTF-8 text (ABI string)
+```
+
+### 4.5 TLV Entry
+
+```
+TLV =
+  tag         u16 BE    Tag identifier (type)
+  length      u32 BE    Number of bytes in the value
+  value       byte[length]  Raw bytes
+```
+
+TLV entries support variable-length values and are skippable by parsers that do not recognize a tag: read the `u32` length and advance by `2 + 4 + length` bytes.
+
+### 4.6 Metadata Tags
+
+| Tag | Name | Value |
+|-----|------|-------|
+| 1 | package | UTF-8 text: package name |
+| 2 | version | UTF-8 text: version string |
+| 3 | description | UTF-8 text: description |
+| 4 | license | UTF-8 text: license identifier or text |
+| 5 | createdBy | UTF-8 text: creator identifier |
+
+Unknown metadata tags are ignored. Unknown extension tags are skipped by length.
+
+### 4.7 Semantic Constraints
+
+A valid bundle manifest must satisfy:
+
+| Constraint | Value |
+|-----------|-------|
+| `schema` | `"arboricx.bundle.manifest.v1"` |
+| `bundleType` | `"tree-calculus-executable-object"` |
+| `treeCalculus` | `"tree-calculus.v1"` |
+| `treeHashAlgorithm` | `"sha256"` |
+| `treeHashDomain` | `"arboricx.merkle.node.v1"` |
+| `treeNodePayload` | `"arboricx.merkle.payload.v1"` |
+| `runtimeSemantics` | `"tree-calculus.v1"` |
+| `runtimeAbi` | `"arboricx.abi.tree.v1"` |
+| `runtimeCapabilities` | Empty array |
+| `closure` | `0` (complete) |
+| `rootCount` | At least 1 |
+| `exportCount` | At least 1 |
+| Export names | Non-empty |
+| Export roots | Non-empty (32 bytes each) |
+
+---
+
+## 5. Section: Nodes (type 2)
+
+The nodes section contains all Merkle DAG nodes referenced by the manifest. It is a sequence of node entries preceded by a count.
+
+```
+NodesSection =
+  nodeCount     u64 BE    Total number of node entries
+  entries       NodeEntry[]
+```
+
+Each node entry:
+
+```
+NodeEntry =
+  hash          32 bytes    Raw SHA-256 hash of this node
+  payloadLen    u32 BE    Length of the payload in bytes
+  payload       byte[payloadLen]  Node payload (see Section 6)
+```
+
+The node count is `u64` to support large bundles. Entries are stored in the order produced by the exporter (typically sorted by hash for determinism).
+
+---
+
+## 6. Merkle Node Payload Format
+
+Each node in the Merkle DAG is one of three types. The payload is a single byte type tag followed by hash references:
+
+### Leaf
+
+```
+Payload = 0x00
+```
+
+A leaf has no children. The payload is exactly 1 byte.
+
+### Stem
+
+```
+Payload = 0x01 || child_hash (32 bytes raw)
+```
+
+A stem has exactly one child. The payload is 33 bytes.
+
+### Fork
+
+```
+Payload = 0x02 || left_hash (32 bytes raw) || right_hash (32 bytes raw)
+```
+
+A fork has exactly two children. The payload is 65 bytes.
+
+**Validation:**
+- Leaf payloads must be exactly 1 byte (`0x00`).
+- Stem payloads must be exactly 33 bytes.
+- Fork payloads must be exactly 65 bytes.
+- Unknown type bytes are rejected.
+
+---
+
+## 7. Merkle Hash Computation
+
+Each node is identified by a SHA-256 hash of its canonical payload:
+
+```
+hash = SHA256( domain_tag || 0x00 || payload )
+```
+
+Where:
+
+| Component | Value |
+|-----------|-------|
+| `domain_tag` | `"arboricx.merkle.node.v1"` as UTF-8 bytes |
+| Separator | `0x00` (one zero byte) |
+| `payload` | The node's canonical serialization from Section 6 |
+
+**Examples:**
+
+- **Leaf:** `SHA256("arboricx.merkle.node.v1" || 0x00 || 0x00)`
+- **Stem:** `SHA256("arboricx.merkle.node.v1" || 0x00 || 0x01 || child_hash_bytes)`
+- **Fork:** `SHA256("arboricx.merkle.node.v1" || 0x00 || 0x02 || left_hash_bytes || right_hash_bytes)`
+
+The resulting SHA-256 hash is stored as a hex-encoded string in the manifest (64 hex characters). Within the nodes section, it is stored as raw bytes.
+
+---
+
+## 8. Tree Calculus Reduction Semantics
+
+The bundle represents a **Tree Calculus** term as a Merkle DAG. The reduction rules are:
+
+### Apply Rules
+
+```
+apply(Fork(Leaf, a), _)          = a
+apply(Fork(Stem(a), b), c)       = apply(apply(a, c), apply(b, c))
+apply(Fork(Fork, _, _), Leaf)    = left of inner Fork
+apply(Fork(Fork, _, _), Stem)    = right of inner Fork
+apply(Fork(Fork, _, _), Fork)    = apply(apply(c, u), v)  where c = Fork(u, v)
+apply(Leaf, b)                   = Stem(b)
+apply(Stem(a), b)                = Fork(a, b)
+```
+
+### Internal Representation
+
+In the reduction engine, Fork nodes use a `[right, left]` (stack) ordering:
+- `Fork = [right_child, left_child]`
+- `Stem = [child]`
+- `Leaf = []`
+
+This ordering supports stack-based reduction: pop two terms, apply, push results back.
+
+### Closure
+
+The bundle declares `closure = "complete"`, meaning all nodes reachable from export roots are present in the nodes section. No external references exist.
+
+---
+
+## 9. Binary Primitives
+
+All multi-byte integers use **big-endian** byte order.
+
+### u16 (2 bytes)
+
+```
+byte[0] | byte[1]
+value = (byte[0] << 8) | byte[1]
+```
+
+### u32 (4 bytes)
+
+```
+byte[0] | byte[1] | byte[2] | byte[3]
+value = (byte[0] << 24) | (byte[1] << 16) | (byte[2] << 8) | byte[3]
+```
+
+### u64 (8 bytes)
+
+```
+byte[0] ... byte[7]
+value = (byte[0] << 56) | ... | byte[7]
+```
+
+### u8 (1 byte)
+
+A single byte, value `0-255`.
+
+---
+
+## 10. Bundle Verification
+
+A complete bundle verification proceeds in this order:
+
+1. **Magic check:** First 8 bytes must be `"ARBORICX"`.
+2. **Version check:** Major version must be `1`.
+3. **Section directory:** Parse all entries; reject unknown critical sections.
+4. **Digest verification:** For each section, compute `SHA256(section_data)` and compare with the digest in the directory entry.
+5. **Manifest parsing:** Decode the fixed-order manifest; validate semantic constraints.
+6. **Node section:** Parse all node entries; reject duplicates.
+7. **Root verification:** All root hashes from the manifest must exist in the node map.
+8. **Export verification:** All export root hashes must exist in the node map.
+9. **Node hash verification:** For each node, compute `SHA256(domain || 0x00 || payload)` and compare with the stored hash.
+10. **Children verification:** For each Stem/Fork node, both child hashes must exist in the node map.
+11. **Closure verification:** Starting from each root hash, traverse the DAG and confirm all reachable nodes are present.
+
+---
+
+## 11. Known Section Types
+
+| Type | Name | Required | Version | Description |
+|------|------|----------|---------|-------------|
+| 1 | Manifest | Yes | 1 | Bundle metadata in fixed-order binary format |
+| 2 | Nodes | Yes | 1 | Merkle DAG node entries |
+
+Unknown section types are permitted if not marked as critical (flags bit 0 is not set).
+
+---
+
+## Appendix A: Complete Example Layout (id.arboricx)
+
+A minimal `id.arboricx` bundle has:
+
+```
++---------------------------------------------------+
+| Header (32 bytes)                                  |
+|   Magic: "ARBORICX"                               |
+|   Major: 1, Minor: 0                              |
+|   Section count: 2                                 |
+|   Flags: 0                                         |
+|   Dir offset: 32                                   |
++---------------------------------------------------+
+| Section Directory (120 bytes = 2 × 60)             |
+|   Entry 0: type=1 (manifest), offset=152, len=375 |
+|   Entry 1: type=2 (nodes),  offset=527, len=284   |
++---------------------------------------------------+
+| Manifest Section (375 bytes)                       |
+|   Magic: "ARBMNFST"                                |
+|   Version: 1.0                                     |
+|   Core strings (schema, bundleType, tree spec,     |
+|   runtime spec, capabilities, closure, roots,      |
+|   exports, metadata TLVs, extension fields)        |
++---------------------------------------------------+
+| Nodes Section (284 bytes)                          |
+|   Node count: 2                                    |
+|   Node entry 1: hash + payload (Leaf)              |
+|   Node entry 2: hash + payload (Fork)              |
++---------------------------------------------------+
+```
+
+The manifest section starts at byte 152 (0x98) and the nodes section at byte 527 (0x20F).
+
+---
+
+## Appendix B: File Extension
+
+Bundles produced by the `tricu` tool use the `.arboricx` file extension. The `.tri` extension is used for plain source files; the `.arboricx` extension identifies the portable binary format.

docs/host-abi.md

@@ -0,0 +1,247 @@
+# tricu Host ABI
+
+This document specifies the first host-facing ABI for self-hosted Arboricx execution.
+
+The ABI is intentionally small. A host language should only need to implement Tree Calculus construction/reduction plus a tiny set of canonical payload codecs. Higher-level execution policy lives in Tree Calculus.
+
+## Goals
+
+- Keep host-language implementations small and auditable.
+- Preserve canonical Tree Calculus representations for payloads.
+- Provide a stable tagged envelope so hosts do not need per-application result conventions.
+- Reuse the existing `ok` / `err` result protocol.
+- Support typed execution wrappers for common return types.
+
+## Non-goals
+
+- This ABI does not remove the need for host codecs entirely.
+- This ABI does not define every possible application protocol.
+- This ABI does not require auto-detecting arbitrary result types.
+
+## Outer result protocol
+
+Host ABI runners return the existing tricu result shape from `lib/binary.tri`:
+
+```tricu
+ok value rest = pair true (pair value rest)
+err code rest = pair false (pair code rest)
+```
+
+On success, `value` is a host ABI value.
+
+On failure, `code` is a canonical Tree Calculus number. The host may report the numeric code and optionally inspect `rest` for debugging.
+
+## Host ABI value shape
+
+A host ABI value is:
+
+```tricu
+pair tag payload
+```
+
+The `tag` says how the host should interpret `payload`.
+
+The payload is always the canonical/raw Tree Calculus representation for that type. The ABI envelope tags the payload; it does not replace or recursively wrap canonical Tree Calculus data.
+
+## Tags
+
+Initial tags:
+
+```tricu
+hostTreeTag   = 0
+hostStringTag = 1
+hostNumberTag = 2
+hostBoolTag   = 3
+hostListTag   = 4
+hostBytesTag  = 5
+```
+
+Planned/error tag, if needed later:
+
+```tricu
+hostErrorTag  = 6
+```
+
+The first implementation keeps errors in the outer `err` result protocol rather than returning `hostError` inside `ok`.
+
+## Constructors
+
+The ABI constructors are:
+
+```tricu
+hostTree value
+hostString bytes
+hostNumber n
+hostBool b
+hostList xs
+hostBytes bytes
+```
+
+Each constructor returns:
+
+```tricu
+pair tag payload
+```
+
+Examples:
+
+```tricu
+hostString "hello"
+hostNumber 42
+hostBool true
+hostList [1 2 3]
+hostTree (t t t)
+```
+
+## Payload conventions
+
+Payloads use existing canonical tricu encodings:
+
+| ABI value | Payload |
+| --- | --- |
+| `hostTree` | arbitrary raw Tree Calculus value |
+| `hostString` | canonical string/byte-list representation |
+| `hostNumber` | canonical tricu number |
+| `hostBool` | canonical tricu bool (`false = t`, `true = t t`) |
+| `hostList` | canonical tricu list (`t` empty, `pair head tail` cons) |
+| `hostBytes` | canonical byte list |
+
+`hostList` payloads are raw canonical lists, **not** lists of host ABI values.
+
+## Accessors / matching
+
+The first ABI should expose simple accessors:
+
+```tricu
+hostValueTag hostValue
+hostValuePayload hostValue
+```
+
+A host can decode the envelope by destructuring the pair directly, but these helpers make the ABI explicit and testable.
+
+## Validation predicates
+
+Typed runners should validate that the raw application result can be interpreted as the requested type before wrapping it.
+
+Initial predicates:
+
+```tricu
+hostNumber? value
+hostBool? value
+hostList? value
+hostString? value
+hostBytes? value
+```
+
+These predicates are structural checks over canonical encodings. They are not general semantic type inference.
+
+Important ambiguity note:
+
+Tree Calculus encodings are not globally disjoint. For example, `t` is also `false`, `0`, and `[]`. Typed runners intentionally interpret values according to the requested type.
+
+## Error behavior
+
+Typed ABI runners return an error if the application result does not match the requested type.
+
+Initial error code:
+
+```tricu
+errHostCodecFailed = 14
+```
+
+Example:
+
+```tricu
+runArboricxToString bundle args
+```
+
+returns:
+
+```tricu
+ok (hostString resultBytes) rest
+```
+
+if `resultBytes` is string-like, otherwise:
+
+```tricu
+err errHostCodecFailed result
+```
+
+where `result` is the raw application result that failed validation.
+
+## Execution wrappers
+
+The base self-hosted Arboricx runners are defined in `lib/arboricx.tri`:
+
+```tricu
+runArboricxArgs bundleBytes args
+runArboricxArgsByName nameBytes bundleBytes args
+```
+
+Host ABI wrappers layer typed output envelopes on top:
+
+```tricu
+runArboricxToTree bundleBytes args
+runArboricxToString bundleBytes args
+runArboricxToNumber bundleBytes args
+runArboricxToBool bundleBytes args
+runArboricxToList bundleBytes args
+runArboricxToBytes bundleBytes args
+```
+
+Named-export variants:
+
+```tricu
+runArboricxByNameToTree nameBytes bundleBytes args
+runArboricxByNameToString nameBytes bundleBytes args
+runArboricxByNameToNumber nameBytes bundleBytes args
+runArboricxByNameToBool nameBytes bundleBytes args
+runArboricxByNameToList nameBytes bundleBytes args
+runArboricxByNameToBytes nameBytes bundleBytes args
+```
+
+## Host usage
+
+For a bundle whose default export is an unapplied function:
+
+```tricu
+append "hello "
+```
+
+A host that expects a string result evaluates:
+
+```tricu
+runArboricxToString bundleBytes ["james"]
+```
+
+On success, the result is:
+
+```tricu
+ok (hostString "hello james") rest
+```
+
+The host then:
+
+1. unwraps `ok`,
+2. checks `hostStringTag`,
+3. decodes the canonical string payload.
+
+## Implementation reference
+
+- Tree constructors, numbers, strings, and lists: `src/Research.hs`
+- Result protocol: `lib/binary.tri`
+- Arboricx parser/executor: `lib/arboricx.tri`
+- Host ABI implementation: `lib/host-abi.tri` or `lib/arboricx.tri`, depending on final organization
+
+## First-pass invariants
+
+Tests should cover these invariants:
+
+1. Each constructor stores the correct tag and payload.
+2. `hostValueTag` and `hostValuePayload` destructure values correctly.
+3. `runArboricxToTree` always wraps successful raw results as `hostTree`.
+4. `runArboricxToString` wraps string-like results as `hostString`.
+5. `runArboricxToNumber` wraps number-like results as `hostNumber`.
+6. `runArboricxToBool` wraps canonical booleans as `hostBool`.
+7. A typed runner returns `errHostCodecFailed` when validation fails.
+8. Named-export typed runners select the requested export before wrapping.

docs/self-hosted-arboricx-host.md

@@ -0,0 +1,483 @@
+# Self-hosted Arboricx Host Prototype
+
+This document describes how to build a minimal host-language shell that can execute Arboricx bundles through the self-hosted tricu Arboricx parser/executor.
+
+The intended reader is an implementation agent building a first prototype in a host language such as PHP. The same approach should generalize to any language with a small Tree Calculus evaluator.
+
+See also: [`docs/host-abi.md`](./host-abi.md) for the precise host-facing ABI value tags and typed runner contract.
+
+## Goal
+
+Build a tiny host program that can:
+
+1. Represent Tree Calculus values.
+2. Reduce/evaluate Tree Calculus terms.
+3. Load or embed the tricu Arboricx runtime kernel.
+4. Read an application `.arboricx` bundle from disk.
+5. Convert host inputs into canonical Tree Calculus values.
+6. Apply the kernel to the application bundle and arguments.
+7. Unwrap a standardized host ABI result.
+8. Decode the host ABI payload back into host values.
+
+A concrete target example:
+
+```tricu
+-- Application bundle root is an unapplied function:
+append "hello "
+```
+
+The host should be able to call that bundle with the host string `"james"` and receive:
+
+```text
+hello james
+```
+
+With the Host ABI layer, the preferred conceptual call is:
+
+```tricu
+runArboricxToString <applicationBundleBytes> ["james"]
+```
+
+This returns:
+
+```tricu
+ok (hostString "hello james") rest
+```
+
+where `runArboricxToString` comes from the self-hosted Arboricx runtime kernel.
+
+## Architectural overview
+
+There are two Arboricx bundles involved:
+
+1. **Kernel bundle**
+   - Contains the self-hosted Arboricx parser/executor written in tricu.
+   - Exposes ergonomic runtime entrypoints such as `runArboricxArgs` and Host ABI entrypoints such as `runArboricxToString`.
+   - This can be hardcoded as a Tree Calculus value in the host, or loaded by a minimal host-side Arboricx parser.
+
+2. **Application bundle**
+   - The bundle the user wants to execute.
+   - Example: a bundle whose exported root is `append "hello "`, waiting for one more string argument.
+   - The host reads this file as raw bytes and encodes those bytes as a Tree Calculus byte list.
+
+The minimal host does **not** need to understand the application bundle format if the kernel is already available as a Tree Calculus value. The host only passes the application bundle bytes to the kernel.
+
+## Required host components
+
+### 1. Tree representation
+
+The host needs a representation for the three Tree Calculus constructors:
+
+```text
+Leaf
+Stem child
+Fork left right
+```
+
+Use whatever is idiomatic for the host language. In PHP, for a prototype, simple classes or tagged arrays are sufficient.
+
+Example shape:
+
+```php
+abstract class T {}
+final class Leaf extends T {}
+final class Stem extends T { public T $child; }
+final class Fork extends T { public T $left; public T $right; }
+```
+
+or tagged arrays:
+
+```php
+['tag' => 'leaf']
+['tag' => 'stem', 'child' => $t]
+['tag' => 'fork', 'left' => $l, 'right' => $r]
+```
+
+The evaluator and codecs only need these three constructors.
+
+### 2. Tree Calculus evaluator
+
+The host must implement Tree Calculus reduction. This is the core VM.
+
+The evaluator should use normal-order evaluation, matching the runtime semantics expected by Arboricx manifests:
+
+```text
+runtimeEvaluation = "normal-order"
+```
+
+The evaluator only needs the Tree Calculus reduction rules. There is no parser requirement for the host prototype if terms are constructed directly as trees.
+
+Implementation notes:
+
+- Evaluation must support application: a tree applied to another tree.
+- In this codebase, application is represented structurally as `Fork function argument` before reduction.
+- The evaluator repeatedly reduces until normal form or until a configured step/fuel limit is reached.
+- Add a fuel limit for the first prototype to avoid infinite reductions during debugging.
+
+Reference implementation locations:
+
+- Haskell evaluator/reduction: `src/Research.hs`
+- JavaScript Arboricx runtime evaluator: `ext/js/src/` if present in the checkout
+
+Use those as references for exact reduction behavior.
+
+### 3. Kernel availability
+
+The host needs access to the self-hosted Arboricx runtime kernel as a Tree Calculus value.
+
+There are two viable bootstrap strategies.
+
+#### Strategy A: hardcode the kernel tree
+
+For the first host prototype, this is recommended.
+
+Workflow:
+
+1. Compile/export the tricu kernel entrypoint as an Arboricx bundle or tree value.
+2. Convert the selected exported kernel function into a host-language Tree Calculus literal.
+3. Commit/embed that literal in the host implementation.
+
+Then the host does not need any Arboricx parser of its own for the kernel. It only needs Tree Calculus reduction.
+
+#### Strategy B: bootstrap the kernel from an Arboricx bundle
+
+Alternatively, the host can implement a minimal Arboricx parser just sufficient to load the kernel bundle.
+
+This is more work up front, but avoids hardcoding a huge tree literal.
+
+If using this strategy, the host-side parser needs to:
+
+1. Parse the Arboricx container.
+2. Parse enough manifest/export data to locate the desired kernel export.
+3. Parse node records.
+4. Reconstruct the selected root Tree Calculus value from the Merkle node DAG.
+
+This logic is exactly what the tricu self-hosted kernel does, so the hardcoded-kernel path is simpler for early ports.
+
+## Kernel entrypoints
+
+The ergonomic runtime API currently lives in `lib/arboricx.tri`.
+
+### Raw execution entrypoints
+
+These return raw application results inside the existing `ok` / `err` result protocol:
+
+```tricu
+readArboricxExecutableByName nameBytes bundleBytes
+readArboricxExecutable bundleBytes
+runArboricxByName nameBytes bundleBytes arg
+runArboricx bundleBytes arg
+runArboricxArgsByName nameBytes bundleBytes args
+runArboricxArgs bundleBytes args
+```
+
+`runArboricxArgs` accepts:
+
+1. Raw application bundle bytes as a Tree Calculus byte list.
+2. A Tree Calculus list of arguments.
+
+For named exports, use `runArboricxArgsByName`, which accepts:
+
+1. Export name as bytes.
+2. Application bundle bytes as bytes.
+3. Argument list.
+
+### Host ABI typed entrypoints
+
+For host-language ports, prefer the Host ABI typed runners. These wrap successful outputs in a tagged host ABI value so every host can decode the same envelope shape.
+
+Default export variants:
+
+```tricu
+runArboricxToTree bundleBytes args
+runArboricxToString bundleBytes args
+runArboricxToNumber bundleBytes args
+runArboricxToBool bundleBytes args
+runArboricxToList bundleBytes args
+runArboricxToBytes bundleBytes args
+```
+
+Named export variants:
+
+```tricu
+runArboricxByNameToTree nameBytes bundleBytes args
+runArboricxByNameToString nameBytes bundleBytes args
+runArboricxByNameToNumber nameBytes bundleBytes args
+runArboricxByNameToBool nameBytes bundleBytes args
+runArboricxByNameToList nameBytes bundleBytes args
+runArboricxByNameToBytes nameBytes bundleBytes args
+```
+
+Recommended first host entrypoint for the `append "hello "` example:
+
+```tricu
+runArboricxToString
+```
+
+## Applying the kernel in the host evaluator
+
+If the host has the Tree Calculus value for `runArboricxToString`, call it by constructing nested application trees.
+
+In Tree Calculus application form:
+
+```text
+((runArboricxToString bundleBytesTree) argsTree)
+```
+
+Structurally, if `app(f, x)` constructs `Fork(f, x)`, then:
+
+```php
+$expr = app(app($kernelRunArboricxToString, $bundleBytesTree), $argsTree);
+$result = normalize($expr);
+```
+
+For named export execution:
+
+```text
+(((runArboricxByNameToString nameBytesTree) bundleBytesTree) argsTree)
+```
+
+Structurally:
+
+```php
+$expr = app(
+    app(
+        app($kernelRunArboricxByNameToString, $nameBytesTree),
+        $bundleBytesTree
+    ),
+    $argsTree
+);
+$result = normalize($expr);
+```
+
+## Result convention and Host ABI envelope
+
+All runtime APIs return the existing tricu `ok` / `err` convention from `lib/binary.tri`:
+
+```tricu
+ok value rest = pair true (pair value rest)
+err code rest = pair false (pair code rest)
+```
+
+The host should always unwrap this outer result first.
+
+### Raw runners
+
+Raw runners such as `runArboricxArgs` return:
+
+```tricu
+ok rawApplicationValue rest
+```
+
+The host must know how to interpret `rawApplicationValue`.
+
+### Host ABI typed runners
+
+Typed runners such as `runArboricxToString` return:
+
+```tricu
+ok hostAbiValue rest
+```
+
+A host ABI value has shape:
+
+```tricu
+pair tag payload
+```
+
+The payload is still the canonical/raw Tree Calculus representation for that type.
+
+Initial tags are specified in [`docs/host-abi.md`](./host-abi.md):
+
+```tricu
+hostTreeTag   = 0
+hostStringTag = 1
+hostNumberTag = 2
+hostBoolTag   = 3
+hostListTag   = 4
+hostBytesTag  = 5
+```
+
+For example:
+
+```tricu
+runArboricxToString bundleBytes ["james"]
+```
+
+returns:
+
+```tricu
+ok (hostString "hello james") rest
+```
+
+which is structurally:
+
+```tricu
+ok (pair hostStringTag "hello james") rest
+```
+
+### Error shape
+
+Expected error shape:
+
+```tricu
+err code rest
+```
+
+The error code is a Tree Calculus number. Error constants are defined in:
+
+- `lib/binary.tri`
+- `lib/arboricx-common.tri`
+- `lib/arboricx.tri` for Host ABI codec errors, currently `errHostCodecFailed = 14`
+
+Typed runners return `errHostCodecFailed` if the application result cannot be interpreted as the requested type.
+
+A prototype host can report the numeric error code and optionally dump a compact representation of `rest`.
+
+## Example execution flow
+
+Suppose the application bundle exports this root:
+
+```tricu
+append "hello "
+```
+
+The bundle root is an unapplied function waiting for one more string argument.
+
+Host flow:
+
+1. Load kernel entrypoint tree:
+
+   ```php
+   $runArboricxToString = loadHardcodedKernelEntrypoint('runArboricxToString');
+   ```
+
+2. Read application bundle bytes:
+
+   ```php
+   $bytes = file_get_contents('append-hello.arboricx');
+   ```
+
+3. Encode bundle bytes as a Tree Calculus byte list:
+
+   ```php
+   $bundleBytesTree = encodeBytes($bytes);
+   ```
+
+4. Encode host argument(s):
+
+   ```php
+   $arg = encodeString('james');
+   $args = encodeList([$arg]);
+   ```
+
+5. Build application expression:
+
+   ```php
+   $expr = app(app($runArboricxToString, $bundleBytesTree), $args);
+   ```
+
+6. Evaluate:
+
+   ```php
+   $result = normalize($expr);
+   ```
+
+7. Unwrap `ok` result:
+
+   ```php
+   [$ok, $hostValue, $rest] = unwrapResult($result);
+   if (!$ok) { throw new RuntimeException('Arboricx error'); }
+   ```
+
+8. Unwrap Host ABI envelope:
+
+   ```php
+   [$tag, $payload] = unwrapHostValue($hostValue);
+   if ($tag !== HOST_STRING_TAG) { throw new RuntimeException('Expected string'); }
+   ```
+
+9. Decode the payload:
+
+   ```php
+   echo decodeString($payload); // hello james
+   ```
+
+## What the kernel does internally
+
+`runArboricxToString` performs the following steps inside Tree Calculus:
+
+1. Parse and validate the raw Arboricx bundle bytes.
+2. Parse the manifest.
+3. Select the default export:
+   - use export named `main` if present,
+   - otherwise use the sole export if exactly one exists,
+   - otherwise return an error.
+4. Read the nodes section.
+5. Reconstruct the selected root tree from the Merkle DAG.
+6. Apply each host-provided argument in order.
+7. Validate that the raw result is string-like.
+8. Return `ok (hostString result) rest`, or an `err`.
+
+`runArboricxByNameToString` is identical except that it selects a named export.
+
+Other typed runners follow the same pattern for their requested output type.
+
+## Tests proving the expected behavior
+
+The relevant Haskell tests are in `test/Spec.hs` under `manifestReadingTests`.
+
+Important cases:
+
+- `readArboricxExecutable: reconstructs default export tree`
+- `readArboricxExecutableByName: selects named export`
+- `runArboricx: applies host-provided argument to default export`
+- `runArboricxArgs: applies host-provided argument list in order`
+- `host ABI: constructors expose tag and payload`
+- `runArboricxToTree: wraps raw result as hostTree`
+- `runArboricxToString: wraps string result as hostString`
+- `runArboricxToNumber: wraps number result as hostNumber`
+- `runArboricxToBool: rejects non-bool result`
+
+These tests demonstrate the host-shell contract:
+
+- application bundle bytes are supplied as a Tree Calculus byte list,
+- host arguments are supplied as canonical Tree Calculus values,
+- execution returns an outer result-wrapped value,
+- Host ABI typed runners return a tagged ABI envelope inside `ok`.
+
+## Minimal PHP prototype checklist
+
+A PHP prototype should implement:
+
+- [ ] Tree data constructors: `Leaf`, `Stem`, `Fork`.
+- [ ] Application helper: `app($f, $x) = Fork($f, $x)`.
+- [ ] Normal-order Tree Calculus reducer.
+- [ ] Fuel/step limit for debugging.
+- [ ] Hardcoded kernel entrypoint tree for `runArboricxToString` for the first string-output prototype.
+- [ ] Encode application bundle file bytes into a Tree Calculus byte list.
+- [ ] Encode host argument values into Tree Calculus values.
+- [ ] Build expression: `((runArboricxToString bundleBytes) args)`.
+- [ ] Normalize expression.
+- [ ] Unwrap outer `ok` / `err` result.
+- [ ] Unwrap Host ABI `pair tag payload` envelope.
+- [ ] Decode payload according to tag.
+
+For exact codec details, reference the Haskell implementation in `src/Research.hs` and the existing JS runtime if available.
+
+## Current recommendation
+
+For the first PHP implementation:
+
+1. Hardcode only the `runArboricxToString` kernel entrypoint as a Tree Calculus value.
+2. Do not implement host-side Arboricx parsing yet.
+3. Implement only enough codecs for:
+   - bytes,
+   - strings,
+   - lists,
+   - result unwrapping,
+   - Host ABI envelope unwrapping.
+4. Use one test fixture: an Arboricx bundle whose root is `append "hello "`.
+5. Assert that calling it with `"james"` returns an outer `ok`, then a `hostString`, then payload `"hello james"`.
+
+Once that works, add named export support via `runArboricxByNameToString` and expand Host ABI tags/codecs as needed.

ext/js/package.json

@@ -0,0 +1,17 @@
+{
+  "name": "arboricx-runtime",
+  "version": "0.1.0",
+  "description": "Arboricx portable bundle runtime — JavaScript reference implementation",
+  "type": "module",
+  "main": "src/bundle.js",
+  "bin": {
+    "arboricx-run": "src/cli.js"
+  },
+  "scripts": {
+    "test": "node --test test/*.test.js",
+    "inspect": "node src/cli.js inspect",
+    "run": "node src/cli.js run"
+  },
+  "keywords": ["arboricx", "tree-calculus", "trie", "runtime"],
+  "license": "MIT"
+}

ext/js/src/bundle.js

@@ -0,0 +1,191 @@
+/**
+ * bundle.js — Parse an Arboricx portable bundle binary into a JavaScript object.
+ *
+ * Format (v1):
+ *   Header (32 bytes):
+ *     Magic        8B  "ARBORICX"
+ *     Major        2B  u16 BE  (must be 1)
+ *     Minor        2B  u16 BE
+ *     SectionCount 4B  u32 BE
+ *     Flags        8B  u64 BE
+ *     DirOffset    8B  u64 BE
+ *   Section Directory (SectionCount × 60 bytes):
+ *     Type          4B  u32 BE
+ *     Version       2B  u16 BE
+ *     Flags         2B  u16 BE  (bit 0 = critical)
+ *     Compression   2B  u16 BE
+ *     DigestAlgo    2B  u16 BE
+ *     Offset        8B  u64 BE
+ *     Length        8B  u64 BE
+ *     SHA256Digest 32B raw
+ *   Manifest: fixed-order core + TLV tail (ARBMNFST magic)
+ *   Nodes: binary section
+ */
+
+import { createHash } from "node:crypto";
+import { decodeManifest } from "./manifest.js";
+
+// ── Constants ───────────────────────────────────────────────────────────────
+
+const MAGIC = Buffer.from([0x41, 0x52, 0x42, 0x4f, 0x52, 0x49, 0x43, 0x58]); // "ARBORICX"
+const HEADER_LENGTH = 32;
+const SECTION_ENTRY_LENGTH = 60;
+const SECTION_MANIFEST = 1;
+const SECTION_NODES = 2;
+const FLAG_CRITICAL = 0x0001;
+const COMPRESSION_NONE = 0;
+const DIGEST_SHA256 = 1;
+const MAJOR_VERSION = 1;
+const MINOR_VERSION = 0;
+
+// ── Helpers ─────────────────────────────────────────────────────────────────
+
+function readU16BE(buf, offset) {
+  return buf.readUint16BE(offset);
+}
+function readU32BE(buf, offset) {
+  return buf.readUint32BE(offset);
+}
+function readU64BE(buf, offset) {
+  return buf.readBigUInt64BE(offset);
+}
+
+function sha256(data) {
+  return createHash("sha256").update(data).digest();
+}
+
+// ── Public API ──────────────────────────────────────────────────────────────
+
+/**
+ * Parse a bundle Buffer into a Bundle object.
+ *
+ * Returns { version, sectionCount, sections } where sections maps
+ * section type numbers to parsed section info (offset, length, data).
+ */
+export function parseBundle(buffer) {
+  if (buffer.length < HEADER_LENGTH) {
+    throw new Error("bundle too short for header");
+  }
+
+  // Check magic
+  if (!buffer.slice(0, 8).equals(MAGIC)) {
+    throw new Error("invalid magic: expected ARBORICX");
+  }
+
+  // Parse header
+  const major = readU16BE(buffer, 8);
+  const minor = readU16BE(buffer, 10);
+  const sectionCount = readU32BE(buffer, 12);
+
+  if (major !== MAJOR_VERSION) {
+    throw new Error(
+      `unsupported bundle major version: ${major} (expected ${MAJOR_VERSION})`
+    );
+  }
+
+  const dirOffset = Number(readU64BE(buffer, 24));
+
+  // Parse section directory
+  const dirStart = dirOffset;
+  const dirEnd = dirStart + sectionCount * SECTION_ENTRY_LENGTH;
+
+  if (buffer.length < dirEnd) {
+    throw new Error("bundle truncated in section directory");
+  }
+
+  const entries = [];
+  for (let i = 0; i < sectionCount; i++) {
+    const off = dirStart + i * SECTION_ENTRY_LENGTH;
+    const entry = {
+      type: readU32BE(buffer, off),
+      version: readU16BE(buffer, off + 4),
+      flags: readU16BE(buffer, off + 6),
+      compression: readU16BE(buffer, off + 8),
+      digestAlgorithm: readU16BE(buffer, off + 10),
+      offset: Number(readU64BE(buffer, off + 12)),
+      length: Number(readU64BE(buffer, off + 20)),
+      digest: buffer.slice(off + 28, off + 28 + 32),
+    };
+    entries.push(entry);
+  }
+
+  // Validate sections
+  for (const entry of entries) {
+    const isCritical = (entry.flags & FLAG_CRITICAL) !== 0;
+    const isKnown =
+      entry.type === SECTION_MANIFEST || entry.type === SECTION_NODES;
+    if (isCritical && !isKnown) {
+      throw new Error(`unknown critical section type: ${entry.type}`);
+    }
+    if (entry.compression !== COMPRESSION_NONE) {
+      throw new Error(
+        `unsupported compression codec in section ${entry.type}`
+      );
+    }
+    if (entry.digestAlgorithm !== DIGEST_SHA256) {
+      throw new Error(
+        `unsupported digest algorithm in section ${entry.type}`
+      );
+    }
+  }
+
+  // Verify section digests and extract data
+  const sections = new Map();
+  for (const entry of entries) {
+    if (entry.offset < 0 || entry.length < 0) {
+      throw new Error(`section ${entry.type} has negative offset/length`);
+    }
+    if (buffer.length < entry.offset + entry.length) {
+      throw new Error(
+        `section ${entry.type} extends beyond bundle end`
+      );
+    }
+
+    const data = buffer.slice(entry.offset, entry.offset + entry.length);
+
+    // Verify digest
+    const computed = sha256(data);
+    if (!computed.equals(entry.digest)) {
+      throw new Error(
+        `section digest mismatch for section type ${entry.type}`
+      );
+    }
+
+    sections.set(entry.type, {
+      ...entry,
+      data,
+    });
+  }
+
+  // Check required sections
+  if (!sections.has(SECTION_MANIFEST)) {
+    throw new Error("missing required section: manifest");
+  }
+  if (!sections.has(SECTION_NODES)) {
+    throw new Error("missing required section: nodes");
+  }
+
+  return {
+    version: `${major}.${minor}`,
+    sectionCount,
+    sections,
+  };
+}
+
+/**
+ * Convenience: parse and return the manifest from the fixed-order binary format.
+ */
+export function parseManifest(buffer) {
+  const bundle = parseBundle(buffer);
+  const manifestEntry = bundle.sections.get(SECTION_MANIFEST);
+  return decodeManifest(manifestEntry.data);
+}
+
+/**
+ * Convenience: parse and return the node section binary.
+ */
+export function parseNodeSection(buffer) {
+  const bundle = parseBundle(buffer);
+  const nodesEntry = bundle.sections.get(SECTION_NODES);
+  return nodesEntry.data;
+}

ext/js/src/cli.js

@@ -0,0 +1,249 @@
+#!/usr/bin/env node
+/**
+ * cli.js — Minimal CLI for inspecting and running Arboricx bundles.
+ *
+ * Usage:
+ *   node cli.js inspect <bundle>
+ *   node cli.js run <bundle> [exportName] [input]
+ */
+
+import { readFileSync } from "node:fs";
+import { parseBundle, parseManifest } from "./bundle.js";
+import { parseNodeSection as parseNodeSectionMerkle } from "./merkle.js";
+import {
+  validateManifest,
+  selectExport,
+  printManifestInfo,
+} from "./manifest.js";
+import { parseNodeSection as parseNodeSectionBundle } from "./bundle.js";
+import {
+  verifyNodeHashes,
+  verifyClosure,
+  verifyRootClosure,
+} from "./merkle.js";
+import { isTree, apply, triage, isFork, isStem } from "./tree.js";
+import { decodeResult, formatTree } from "./codecs.js";
+
+// ── Commands ────────────────────────────────────────────────────────────────
+
+function cmdInspect(bundlePath) {
+  const buffer = readFileSync(bundlePath);
+  try {
+    const manifest = parseManifest(buffer);
+    validateManifest(manifest);
+
+    const nodeSectionBytes = parseNodeSectionBundle(buffer);
+    const { nodeMap } = parseNodeSectionMerkle(nodeSectionBytes);
+
+    console.log(`Bundle: ${bundlePath}`);
+    console.log("");
+
+    printManifestInfo(manifest, "  ");
+
+    console.log(`  Nodes: ${nodeMap.size}`);
+
+    // Verify hashes
+    const { verified: hashesOk, mismatches } = verifyNodeHashes(nodeMap);
+    console.log(`  Hash verification: ${hashesOk ? "OK" : "FAIL"}`);
+    for (const m of mismatches) {
+      console.log(`    MISMATCH ${m.type} ${m.hash.substring(0, 16)}... expected ${m.expected.substring(0, 16)}...`);
+    }
+
+    // Verify closure
+    const { complete: closureOk, missing } = verifyClosure(nodeMap);
+    console.log(`  Closure verification: ${closureOk ? "OK" : "FAIL"}`);
+    for (const m of missing) {
+      console.log(`    MISSING ${m.parent.substring(0, 16)}... → ${m.child.substring(0, 16)}...`);
+    }
+
+    // Verify root closure for each export
+    for (const exp of manifest.exports || []) {
+      const { complete, missingRoots } = verifyRootClosure(
+        nodeMap,
+        exp.root
+      );
+      if (!complete) {
+        console.log(
+          `  Root closure for "${exp.name}": FAIL — missing: ${missingRoots
+            .map((r) => r.substring(0, 16) + "...")
+            .join(", ")}`
+        );
+      }
+    }
+
+    console.log("");
+    console.log("Inspection complete.");
+  } catch (e) {
+    console.error(`Error: ${e.message}`);
+    process.exit(1);
+  }
+}
+
+function cmdRun(bundlePath, exportName, inputArg) {
+  const buffer = readFileSync(bundlePath);
+  let result;
+  try {
+    const manifest = parseManifest(buffer);
+    validateManifest(manifest);
+
+    const selectedExport = selectExport(manifest, exportName);
+
+    const nodeSectionBytes = parseNodeSectionBundle(buffer);
+    const { nodeMap } = parseNodeSectionMerkle(nodeSectionBytes);
+
+    // Verify hashes
+    const { verified, mismatches } = verifyNodeHashes(nodeMap);
+    if (!verified) {
+      console.error(
+        `Node hash mismatch:\n  ${mismatches
+          .map((m) => `  ${m.type}: ${m.hash} (expected ${m.expected})`)
+          .join("\n")}`
+      );
+      process.exit(1);
+    }
+
+    // Reconstruct the tree for the selected export
+    const root = buildTreeFromNodeMap(nodeMap, selectedExport.root);
+    if (!isTree(root)) {
+      console.error("Reconstructed root is not a valid tree value");
+      process.exit(1);
+    }
+
+    // Apply input if provided
+    let term = root;
+    if (inputArg !== undefined) {
+      // TODO: parse input (string/number) into a tree
+      // For now, just run the term as-is
+    }
+
+    // Reduce with fuel limit
+    const finalTerm = reduce(term, 1_000_000);
+
+    // Print result as tree calculus form
+    console.log(formatTree(finalTerm));
+  } catch (e) {
+    console.error(`Error: ${e.message}`);
+    process.exit(1);
+  }
+}
+
+// ── Tree reconstruction ─────────────────────────────────────────────────────
+
+/**
+ * Reconstruct a tree from a node map.
+ *
+ * Node map: Map<hexHash, { type, childHash?, leftHash?, rightHash? }>
+ *
+ * Returns the tree representation: [] for Leaf, [child] for Stem, [right, left] for Fork.
+ * Uses memoization to avoid re-processing nodes.
+ */
+export function buildTreeFromNodeMap(nodeMap, hash, memo = new Map()) {
+  if (memo.has(hash)) return memo.get(hash);
+
+  const node = nodeMap.get(hash);
+  if (!node) {
+    throw new Error(`missing node in bundle: ${hash}`);
+  }
+
+  let tree;
+  switch (node.type) {
+    case "leaf":
+      tree = [];
+      break;
+    case "stem":
+      tree = [buildTreeFromNodeMap(nodeMap, node.childHash, memo)];
+      break;
+    case "fork":
+      tree = [
+        buildTreeFromNodeMap(nodeMap, node.rightHash, memo),
+        buildTreeFromNodeMap(nodeMap, node.leftHash, memo),
+      ];
+      break;
+    default:
+      throw new Error(`unknown node type: ${node.type}`);
+  }
+
+  memo.set(hash, tree);
+  return tree;
+}
+
+// ── Reduction ───────────────────────────────────────────────────────────────
+
+/**
+ * Reduce a term to normal form with a fuel limit.
+ * Uses the stack-based approach from the TS evaluator.
+ */
+export function reduce(term, fuel) {
+  const stack = [term];
+  let remaining = fuel;
+
+  while (stack.length >= 2 && remaining-- > 0) {
+    // Pop right (top), then left
+    const b = stack.pop(); // right
+    const a = stack.pop(); // left
+
+    if (stack.length >= 2) {
+      // Push a back for potential further reduction
+      stack.push(a);
+    }
+
+    const result = apply(a, b);
+
+    if (isTree(result)) {
+      // If result is a value, push it. But if it's a Fork/Stem,
+      // we need to push its components for further reduction.
+      if (isFork(result)) {
+        // Push right first (so it's popped second), then left
+        stack.push(result[1]); // left
+        stack.push(result[0]); // right
+      } else if (isStem(result)) {
+        stack.push(result[0]); // child
+      } else {
+        stack.push(result); // Leaf
+      }
+    } else {
+      // Not a tree — push as-is (shouldn't happen after buildTree)
+      stack.push(result);
+    }
+  }
+
+  if (remaining <= 0) {
+    throw new Error("reduction step limit exceeded");
+  }
+
+  if (stack.length === 1) {
+    return stack[0];
+  }
+  return stack[0]; // fallback
+}
+
+// ── Main ────────────────────────────────────────────────────────────────────
+
+const args = process.argv.slice(2);
+const command = args[0];
+
+switch (command) {
+  case "inspect": {
+    if (args.length < 2) {
+      console.error("Usage: node cli.js inspect <bundle>");
+      process.exit(1);
+    }
+    cmdInspect(args[1]);
+    break;
+  }
+  case "run": {
+    if (args.length < 2) {
+      console.error("Usage: node cli.js run <bundle> [exportName] [input]");
+      process.exit(1);
+    }
+    cmdRun(args[1], args[2], args[3]);
+    break;
+  }
+  default:
+    console.log("Arboricx JS Runtime");
+    console.log("");
+    console.log("Usage:");
+    console.log("  node cli.js inspect <bundle>");
+    console.log("  node cli.js run <bundle> [exportName] [input]");
+    break;
+}

ext/js/src/codecs.js

@@ -0,0 +1,135 @@
+/**
+ * codecs.js — Minimal codecs for decoding tree results.
+ *
+ * Implements: decodeResult (from Research.hs)
+ *   - Leaf → "t"
+ *   - Numbers: toNumber
+ *   - Strings: toString
+ *   - Lists: toList
+ *   - Fallback: raw tree format
+ */
+
+// ── toNumber ────────────────────────────────────────────────────────────────
+
+/**
+ * Decode a tree as a binary number (big-endian).
+ * Leaf = 0, Fork(Leaf, rest) = 2*n, Fork(Stem Leaf, rest) = 2*n+1.
+ */
+export function toNumber(t) {
+  if (!Array.isArray(t)) return null;
+  if (t.length === 0) return 0; // Leaf = 0
+  if (t.length !== 2) return null; // must be Fork
+
+  const [right, left] = t;
+  // Fork structure: [right, left]
+  // left child determines bit: Leaf = 0, Stem(Leaf) = 1
+  let bit;
+  if (Array.isArray(left) && left.length === 0) {
+    bit = 0; // Leaf
+  } else if (Array.isArray(left) && left.length === 1) {
+    const child = left[0];
+    if (Array.isArray(child) && child.length === 0) {
+      bit = 1; // Stem(Leaf) = 1
+    } else {
+      return null; // Stem of something other than Leaf
+    }
+  } else {
+    return null;
+  }
+
+  const rest = toNumber(right);
+  if (rest === null) return null;
+
+  return bit + 2 * rest;
+}
+
+// ── toString ────────────────────────────────────────────────────────────────
+
+/**
+ * Decode a tree as a list of numbers (characters).
+ * Fork(x, rest) = x : list.
+ */
+export function toList(t) {
+  if (!Array.isArray(t)) return null;
+  if (t.length === 0) return []; // Leaf = empty list
+  if (t.length !== 2) return null; // must be Fork
+
+  const [right, left] = t;
+  const rest = toList(right);
+  if (rest === null) return null;
+
+  return [left, ...rest];
+}
+
+/**
+ * Decode a tree as a string.
+ */
+export function toString(t) {
+  const list = toList(t);
+  if (list === null) return null;
+  try {
+    return list.map((ch) => String.fromCharCode(ch)).join("");
+  } catch {
+    return null;
+  }
+}
+
+// ── decodeResult ────────────────────────────────────────────────────────────
+
+/**
+ * Decode a tree result using multiple strategies:
+ *   1. Leaf → "t"
+ *   2. String (if all chars are printable)
+ *   3. Number
+ *   4. List
+ *   5. Raw tree format
+ */
+export function decodeResult(t) {
+  if (!Array.isArray(t)) {
+    return String(t);
+  }
+
+  // Leaf
+  if (t.length === 0) {
+    return "t";
+  }
+
+  // Try string first (list of char codes)
+  const list = toList(t);
+  if (list !== null && list.length > 0) {
+    const str = list.map((n) => {
+      if (n < 32 || n > 126) return null;
+      return String.fromCharCode(n);
+    }).join("");
+    if (str) return `"${str}"`;
+  }
+
+  // Try number
+  const num = toNumber(t);
+  if (num !== null) {
+    return String(num);
+  }
+
+  // Try list (elements are trees)
+  if (t.length === 2) {
+    const elements = toList(t);
+    if (elements !== null) {
+      const decoded = elements.map((e) => decodeResult(e));
+      return `[${decoded.join(", ")}]`;
+    }
+  }
+
+  // Raw tree format
+  return formatTree(t);
+}
+
+/**
+ * Format a tree as a parenthesized expression.
+ */
+export function formatTree(t) {
+  if (!Array.isArray(t)) return String(t);
+  if (t.length === 0) return "Leaf";
+  if (t.length === 1) return `Stem(${formatTree(t[0])})`;
+  if (t.length === 2) return `Fork(${formatTree(t[1])}, ${formatTree(t[0])})`;
+  return `[${t.map(formatTree).join(", ")}]`;
+}

ext/js/src/manifest.js

@@ -0,0 +1,374 @@
+/**
+ * manifest.js — Fixed-order manifest parsing and export lookup.
+ *
+ * The manifest binary format (ManifestV1):
+ *   magic(8) + major(u16) + minor(u16)
+ *   + schema(string) + bundleType(string)
+ *   + treeCalculus(string) + treeHashAlgorithm(string) + treeHashDomain(string) + treeNodePayload(string)
+ *   + runtimeSemantics(string) + runtimeEvaluation(string) + runtimeAbi(string)
+ *   + capabilityCount(u32) + capabilities(string[])
+ *   + closure(u8)
+ *   + rootCount(u32) + roots[]
+ *   + exportCount(u32) + exports[]
+ *   + metadataFieldCount(u32) + metadataTLVs[]
+ *   + extensionFieldCount(u32) + extensionTLVs[]
+ *
+ * String format: u32 BE length + UTF-8 bytes.
+ * Root: 32 bytes raw hash + role(string).
+ * Export: name(string) + 32 bytes raw root hash + kind(string) + abi(string).
+ * TLV: u16 tag + u32 length + value bytes.
+ */
+
+// ── Constants ───────────────────────────────────────────────────────────────
+
+const MANIFEST_MAGIC = "ARBMNFST";
+const MANIFEST_MAJOR = 1;
+const MANIFEST_MINOR = 0;
+
+// Metadata TLV tags
+const TAG_PACKAGE = 1;
+const TAG_VERSION = 2;
+const TAG_DESCRIPTION = 3;
+const TAG_LICENSE = 4;
+const TAG_CREATED_BY = 5;
+
+// Closure bytes
+const CLOSURE_COMPLETE = 0;
+const CLOSURE_PARTIAL = 1;
+
+// ── Binary helpers ──────────────────────────────────────────────────────────
+
+function u16(buf, off) {
+  if (off + 2 > buf.length) throw new Error("manifest: not enough bytes for u16");
+  return { value: buf.readUint16BE(off), next: off + 2 };
+}
+
+function u32(buf, off) {
+  if (off + 4 > buf.length) throw new Error("manifest: not enough bytes for u32");
+  return { value: buf.readUint32BE(off), next: off + 4 };
+}
+
+function u8(buf, off) {
+  if (off >= buf.length) throw new Error("manifest: not enough bytes for u8");
+  return { value: buf.readUint8(off), next: off + 1 };
+}
+
+/**
+ * Read a length-prefixed UTF-8 string: u32 BE length + UTF-8 bytes.
+ * Returns { text, next }.
+ */
+function readStr(buf, off) {
+  const { value: len, next: afterLen } = u32(buf, off);
+  if (afterLen + len > buf.length) throw new Error("manifest: string extends beyond input");
+  return { text: buf.toString("utf-8", afterLen, afterLen + len), next: afterLen + len };
+}
+
+/**
+ * Read raw bytes of given length.
+ * Returns { bytes, next }.
+ */
+function readRaw(buf, off, n) {
+  if (off + n > buf.length) throw new Error(`manifest: not enough bytes for ${n}-byte read`);
+  return { value: buf.slice(off, off + n), next: off + n };
+}
+
+// ── Manifest decoder ────────────────────────────────────────────────────────
+
+/**
+ * Decode the manifest binary from a Buffer.
+ *
+ * Returns a normalized manifest object matching the shape expected
+ * by validateManifest / selectExport.
+ */
+export function decodeManifest(buf) {
+  let off = 0;
+
+  // Magic (8 bytes)
+  const magic = buf.toString("utf-8", 0, 8);
+  if (magic !== MANIFEST_MAGIC) {
+    throw new Error(`invalid manifest magic: expected ${MANIFEST_MAGIC}, got "${magic}"`);
+  }
+  off = 8;
+
+  // Version
+  const { value: major } = u16(buf, off);
+  if (major !== MANIFEST_MAJOR) throw new Error(`unsupported manifest major version: ${major}`);
+  off += 4; // u16 major + u16 minor
+
+  // Helper: read length-prefixed text
+  const readText = () => {
+    const { text, next } = readStr(buf, off);
+    off = next;
+    return text;
+  };
+
+  // Core strings
+  const schema = readText();
+  const bundleType = readText();
+  const treeCalculus = readText();
+  const treeHashAlgorithm = readText();
+  const treeHashDomain = readText();
+  const treeNodePayload = readText();
+  const runtimeSemantics = readText();
+  const runtimeEvaluation = readText();
+  const runtimeAbi = readText();
+
+  // Capabilities (u32 count + string[])
+  const { value: capCount } = u32(buf, off);
+  off += 4;
+  const capabilities = [];
+  for (let i = 0; i < capCount; i++) {
+    capabilities.push(readText());
+  }
+
+  // Closure (u8)
+  const { value: closureByte } = u8(buf, off);
+  off += 1;
+  const closure = closureByte === CLOSURE_COMPLETE ? "complete" : "partial";
+
+  // Roots (u32 count + Root[])
+  // Root: 32 bytes raw hash + role(string)
+  const { value: rootCount } = u32(buf, off);
+  off += 4;
+  const roots = [];
+  for (let i = 0; i < rootCount; i++) {
+    const { value: hashRaw } = readRaw(buf, off, 32);
+    off += 32;
+    const { text: role, next: rOff } = readStr(buf, off);
+    off = rOff;
+    roots.push({ hash: hashRaw.toString("hex"), role });
+  }
+
+  // Exports (u32 count + Export[])
+  // Export: name(string) + 32 bytes raw root hash + kind(string) + abi(string)
+  const { value: exportCount } = u32(buf, off);
+  off += 4;
+  const exports = [];
+  for (let i = 0; i < exportCount; i++) {
+    const { text: name, next: nOff } = readStr(buf, off);
+    off = nOff;
+    const { value: expHashRaw } = readRaw(buf, off, 32);
+    off += 32;
+    const { text: kind, next: kOff } = readStr(buf, off);
+    off = kOff;
+    const { text: abi, next: aOff } = readStr(buf, off);
+    off = aOff;
+    exports.push({ name, root: expHashRaw.toString("hex"), kind, abi });
+  }
+
+  // Metadata (u32 count + TLV[])
+  // TLV: u16 tag + u32 length + value bytes
+  const { value: metaCount } = u32(buf, off);
+  off += 4;
+  const metadata = {};
+  for (let i = 0; i < metaCount; i++) {
+    const { value: tag } = u16(buf, off);
+    off += 2;
+    const { value: tlvLen } = u32(buf, off);
+    off += 4;
+    const { value: tlvRaw } = readRaw(buf, off, tlvLen);
+    off += tlvLen;
+    const val = tlvRaw.toString("utf-8");
+    switch (tag) {
+      case TAG_PACKAGE: metadata.package = val; break;
+      case TAG_VERSION: metadata.version = val; break;
+      case TAG_DESCRIPTION: metadata.description = val; break;
+      case TAG_LICENSE: metadata.license = val; break;
+      case TAG_CREATED_BY: metadata.createdBy = val; break;
+    }
+  }
+
+  // Extensions (u32 count + TLV[] — skip all)
+  const { value: extCount } = u32(buf, off);
+  off += 4;
+  for (let i = 0; i < extCount; i++) {
+    const { value: _tag } = u16(buf, off);
+    off += 2;
+    const { value: tlvLen } = u32(buf, off);
+    off += 4;
+    off += tlvLen; // skip value
+  }
+
+  return {
+    schema,
+    bundleType,
+    tree: {
+      calculus: treeCalculus,
+      nodeHash: {
+        algorithm: treeHashAlgorithm,
+        domain: treeHashDomain,
+      },
+      nodePayload: treeNodePayload,
+    },
+    runtime: {
+      semantics: runtimeSemantics,
+      evaluation: runtimeEvaluation,
+      abi: runtimeAbi,
+      capabilities,
+    },
+    closure,
+    roots,
+    exports,
+    metadata: Object.keys(metadata).length > 0 ? metadata : undefined,
+  };
+}
+
+// ── Validation ──────────────────────────────────────────────────────────────
+
+/**
+ * Validate the manifest against the runtime profile requirements.
+ * Throws on violation.
+ */
+export function validateManifest(manifest) {
+  if (manifest.schema !== "arboricx.bundle.manifest.v1") {
+    throw new Error(
+      `unsupported manifest schema: ${manifest.schema}`
+    );
+  }
+  if (manifest.bundleType !== "tree-calculus-executable-object") {
+    throw new Error(
+      `unsupported bundle type: ${manifest.bundleType}`
+    );
+  }
+
+  const tree = manifest.tree;
+  if (tree.calculus !== "tree-calculus.v1") {
+    throw new Error(`unsupported calculus: ${tree.calculus}`);
+  }
+  if (tree.nodeHash.algorithm !== "sha256") {
+    throw new Error(
+      `unsupported node hash algorithm: ${tree.nodeHash.algorithm}`
+    );
+  }
+  if (tree.nodeHash.domain !== "arboricx.merkle.node.v1") {
+    throw new Error(
+      `unsupported node hash domain: ${tree.nodeHash.domain}`
+    );
+  }
+  if (tree.nodePayload !== "arboricx.merkle.payload.v1") {
+    throw new Error(`unsupported node payload: ${tree.nodePayload}`);
+  }
+
+  const runtime = manifest.runtime;
+  if (runtime.semantics !== "tree-calculus.v1") {
+    throw new Error(`unsupported runtime semantics: ${runtime.semantics}`);
+  }
+  if (runtime.abi !== "arboricx.abi.tree.v1") {
+    throw new Error(`unsupported runtime ABI: ${runtime.abi}`);
+  }
+  if (runtime.capabilities && runtime.capabilities.length > 0) {
+    throw new Error(
+      `host/runtime capabilities not supported: ${runtime.capabilities.join(", ")}`
+    );
+  }
+
+  if (manifest.closure !== "complete") {
+    throw new Error("bundle v1 requires closure = complete");
+  }
+  if (manifest.imports && manifest.imports.length > 0) {
+    throw new Error("bundle v1 requires an empty imports list");
+  }
+  if (!manifest.roots || manifest.roots.length === 0) {
+    throw new Error("manifest has no roots");
+  }
+  if (!manifest.exports || manifest.exports.length === 0) {
+    throw new Error("manifest has no exports");
+  }
+
+  for (const exp of manifest.exports) {
+    if (!exp.name) {
+      throw new Error("manifest export has empty name");
+    }
+    if (!exp.root) {
+      throw new Error("manifest export has empty root");
+    }
+  }
+}
+
+/**
+ * Select an export hash given a requested name.
+ *
+ * Selection strategy:
+ *   1. Explicit export name
+ *   2. Export named "main"
+ *   3. Single export (auto-select)
+ *   4. Error if multiple exports and no "main"
+ */
+export function selectExport(manifest, requestedName) {
+  const exports = manifest.exports || [];
+
+  // Strategy 1: explicit name
+  if (requestedName) {
+    const found = exports.find((e) => e.name === requestedName);
+    if (found) {
+      return found;
+    }
+    throw new Error(
+      `requested export "${requestedName}" not found. Available: ${exports.map((e) => e.name).join(", ")}`
+    );
+  }
+
+  // Strategy 2: prefer "main"
+  const mainExport = exports.find((e) => e.name === "main");
+  if (mainExport) {
+    return mainExport;
+  }
+
+  // Strategy 3: single export
+  if (exports.length === 1) {
+    return exports[0];
+  }
+
+  // Strategy 4: multiple exports, require explicit
+  throw new Error(
+    `multiple exports available but none named "main": ${exports.map((e) => e.name).join(", ")}. Specify an export name.`
+  );
+}
+
+/**
+ * Get all root hashes from the manifest.
+ */
+export function getRootHashes(manifest) {
+  return (manifest.roots || []).map((r) => r.hash);
+}
+
+/**
+ * Get all export names.
+ */
+export function getExportNames(manifest) {
+  return (manifest.exports || []).map((e) => e.name);
+}
+
+/**
+ * Print manifest summary info.
+ */
+export function printManifestInfo(manifest, indent = "") {
+  const tree = manifest.tree;
+  const runtime = manifest.runtime;
+
+  console.log(`${indent}Schema:          ${manifest.schema}`);
+  console.log(`${indent}Bundle type:     ${manifest.bundleType}`);
+  console.log(`${indent}Closure:         ${manifest.closure}`);
+  console.log(`${indent}Tree calculus:   ${tree.calculus}`);
+  console.log(`${indent}Hash algo:       ${tree.nodeHash.algorithm}`);
+  console.log(`${indent}Hash domain:     ${tree.nodeHash.domain}`);
+  console.log(`${indent}Runtime:         ${runtime.semantics}`);
+  console.log(`${indent}ABI:             ${runtime.abi}`);
+  console.log(`${indent}Evaluation:      ${runtime.evaluation || "N/A"}`);
+  console.log("");
+  console.log(`${indent}Roots (${getRootHashes(manifest).length}):`);
+  for (const root of getRootHashes(manifest)) {
+    console.log(`${indent}  ${root.substring(0, 16)}...`);
+  }
+  console.log("");
+  console.log(`${indent}Exports (${getExportNames(manifest).length}):`);
+  for (const name of getExportNames(manifest)) {
+    console.log(`${indent}  ${name}`);
+  }
+
+  const meta = manifest.metadata;
+  if (meta && meta.createdBy) {
+    console.log("");
+    console.log(`${indent}Created by:      ${meta.createdBy}`);
+  }
+}

ext/js/src/merkle.js

@@ -0,0 +1,276 @@
+/**
+ * merkle.js — Node payload decoding and hash verification.
+ *
+ * Node payload format:
+ *   Leaf: 0x00
+ *   Stem: 0x01 || child_hash (32 bytes raw)
+ *   Fork: 0x02 || left_hash (32 bytes raw) || right_hash (32 bytes raw)
+ *
+ * Hash computation:
+ *   hash = SHA256( "arboricx.merkle.node.v1" || 0x00 || node_payload )
+ */
+
+import { createHash } from "node:crypto";
+
+// ── Constants ───────────────────────────────────────────────────────────────
+
+const DOMAIN_TAG = "arboricx.merkle.node.v1";
+const HASH_LENGTH = 32; // raw hash bytes
+const HEX_LENGTH = 64;  // hex-encoded hash length
+
+// ── Helpers ─────────────────────────────────────────────────────────────────
+
+function rawToHex(buf) {
+  if (buf.length !== HASH_LENGTH) {
+    throw new Error(`raw hash must be ${HASH_LENGTH} bytes, got ${buf.length}`);
+  }
+  return buf.toString("hex");
+}
+
+function hexToRaw(hex) {
+  const buf = Buffer.from(hex, "hex");
+  if (buf.length !== HASH_LENGTH) {
+    throw new Error(`hex hash must decode to ${HASH_LENGTH} bytes`);
+  }
+  return buf;
+}
+
+function sha256(data) {
+  return createHash("sha256").update(data).digest();
+}
+
+function nodeHash(prefix, payload) {
+  return sha256(Buffer.concat([Buffer.from(prefix), Buffer.from([0x00]), payload]));
+}
+
+// ── Node payload types ──────────────────────────────────────────────────────
+
+/**
+ * Deserialize a node payload into { type, childHash, leftHash, rightHash }.
+ *
+ * type: "leaf" | "stem" | "fork"
+ * childHash: hex string (for stem)
+ * leftHash: hex string (for fork)
+ * rightHash: hex string (for fork)
+ */
+export function deserializePayload(payload) {
+  if (payload.length === 0) {
+    throw new Error("empty payload");
+  }
+
+  const type = payload.readUInt8(0);
+
+  switch (type) {
+    case 0x00:
+      if (payload.length !== 1) {
+        throw new Error(
+          `invalid leaf payload: expected 1 byte, got ${payload.length}`
+        );
+      }
+      return { type: "leaf" };
+
+    case 0x01:
+      if (payload.length !== 1 + HASH_LENGTH) {
+        throw new Error(
+          `invalid stem payload: expected ${1 + HASH_LENGTH} bytes, got ${payload.length}`
+        );
+      }
+      return {
+        type: "stem",
+        childHash: rawToHex(payload.slice(1, 1 + HASH_LENGTH)),
+      };
+
+    case 0x02:
+      if (payload.length !== 1 + 2 * HASH_LENGTH) {
+        throw new Error(
+          `invalid fork payload: expected ${1 + 2 * HASH_LENGTH} bytes, got ${payload.length}`
+        );
+      }
+      return {
+        type: "fork",
+        leftHash: rawToHex(payload.slice(1, 1 + HASH_LENGTH)),
+        rightHash: rawToHex(payload.slice(1 + HASH_LENGTH, 1 + 2 * HASH_LENGTH)),
+      };
+
+    default:
+      throw new Error(
+        `invalid merkle node payload: unknown type 0x${type.toString(16)}`
+      );
+  }
+}
+
+/**
+ * Compute the canonical payload bytes for a given tree node structure.
+ */
+export function serializeNode(node) {
+  switch (node.type) {
+    case "leaf":
+      return Buffer.from([0x00]);
+    case "stem":
+      return Buffer.concat([Buffer.from([0x01]), hexToRaw(node.childHash)]);
+    case "fork":
+      return Buffer.concat([
+        Buffer.from([0x02]),
+        hexToRaw(node.leftHash),
+        hexToRaw(node.rightHash),
+      ]);
+  }
+}
+
+/**
+ * Compute the Merkle hash of a node from its type and parameters.
+ */
+export function computeNodeHash(node) {
+  const payload = serializeNode(node);
+  const hash = nodeHash(DOMAIN_TAG, payload);
+  return hash.toString("hex");
+}
+
+// ── Node section parsing ────────────────────────────────────────────────────
+
+/**
+ * Parse the node section binary into a Map<hexHash, { type, payload, node }>.
+ *
+ * Node section format:
+ *   nodeCount (8B u64 BE)
+ *   entries[]:
+ *     hash (32B raw)
+ *     payloadLen (4B u32 BE)
+ *     payload (payloadLen bytes)
+ */
+export function parseNodeSection(data) {
+  if (data.length < 8) {
+    throw new Error("node section too short for count");
+  }
+
+  const nodeCount = Number(data.readBigUInt64BE(0));
+  let offset = 8;
+
+  const nodeMap = new Map();
+  const errors = [];
+
+  for (let i = 0; i < nodeCount; i++) {
+    // Read hash
+    if (offset + HASH_LENGTH > data.length) {
+      errors.push(`node ${i}: not enough bytes for hash`);
+      break;
+    }
+    const hash = rawToHex(data.slice(offset, offset + HASH_LENGTH));
+    offset += HASH_LENGTH;
+
+    // Read payload length
+    if (offset + 4 > data.length) {
+      errors.push(`node ${i} (${hash}): not enough bytes for payload length`);
+      break;
+    }
+    const payloadLen = data.readUint32BE(offset);
+    offset += 4;
+
+    // Read payload
+    if (offset + payloadLen > data.length) {
+      errors.push(`node ${i} (${hash}): payload extends beyond section end`);
+      break;
+    }
+    const payload = data.slice(offset, offset + payloadLen);
+    offset += payloadLen;
+
+    // Deserialize payload
+    let node;
+    try {
+      node = deserializePayload(payload);
+    } catch (e) {
+      errors.push(`node ${i} (${hash}): ${e.message}`);
+      continue;
+    }
+
+    nodeMap.set(hash, {
+      hash,
+      payload,
+      ...node,
+    });
+  }
+
+  if (errors.length > 0) {
+    throw new Error(
+      `node section parse errors:\n  ${errors.join("\n  ")}`
+    );
+  }
+
+  return { nodeMap, count: nodeCount };
+}
+
+// ── Verification ────────────────────────────────────────────────────────────
+
+/**
+ * Verify all node hashes match their payloads.
+ * Returns { verified, mismatches }
+ */
+export function verifyNodeHashes(nodeMap) {
+  const mismatches = [];
+
+  for (const [hash, node] of nodeMap) {
+    const expected = computeNodeHash(node);
+    if (hash !== expected) {
+      mismatches.push({
+        hash,
+        expected,
+        type: node.type,
+      });
+    }
+  }
+
+  return { verified: mismatches.length === 0, mismatches };
+}
+
+/**
+ * Verify that all child references exist in the node map (closure).
+ * Returns { complete, missing } where missing is an array of { parent, child }.
+ */
+export function verifyClosure(nodeMap) {
+  const missing = [];
+
+  for (const [hash, node] of nodeMap) {
+    if (node.type === "stem") {
+      if (!nodeMap.has(node.childHash)) {
+        missing.push({ parent: hash, child: node.childHash });
+      }
+    } else if (node.type === "fork") {
+      if (!nodeMap.has(node.leftHash)) {
+        missing.push({ parent: hash, child: node.leftHash });
+      }
+      if (!nodeMap.has(node.rightHash)) {
+        missing.push({ parent: hash, child: node.rightHash });
+      }
+    }
+  }
+
+  return { complete: missing.length === 0, missing };
+}
+
+/**
+ * Verify closure for a specific root hash (transitive reachability).
+ * Returns { complete, missingRoots }.
+ */
+export function verifyRootClosure(nodeMap, rootHash) {
+  const visited = new Set();
+  const missingRoots = [];
+
+  function visit(hash) {
+    if (visited.has(hash)) return;
+    if (!nodeMap.has(hash)) {
+      missingRoots.push(hash);
+      return;
+    }
+    visited.add(hash);
+    const node = nodeMap.get(hash);
+    if (node.type === "stem") {
+      visit(node.childHash);
+    } else if (node.type === "fork") {
+      visit(node.leftHash);
+      visit(node.rightHash);
+    }
+  }
+
+  visit(rootHash);
+  return { complete: missingRoots.length === 0, missingRoots };
+}

ext/js/src/tree.js

@@ -0,0 +1,125 @@
+/**
+ * tree.js — Runtime tree representation.
+ *
+ * The JS tree uses a simple array representation matching the
+ * TypeScript reference evaluator:
+ *
+ *   Leaf  = []
+ *   Stem  = [child]          (array length === 1)
+ *   Fork  = [right, left]    (array length === 2)
+ *
+ * This is a "flattened stack" representation: when reduced, terms
+ * become arrays and the evaluator pops three elements at a time.
+ */
+
+/**
+ * Check if a value is a Leaf (empty array).
+ */
+export function isLeaf(t) {
+  return Array.isArray(t) && t.length === 0;
+}
+
+/**
+ * Check if a value is a Stem (single element array).
+ */
+export function isStem(t) {
+  return Array.isArray(t) && t.length === 1;
+}
+
+/**
+ * Check if a value is a Fork (two element array).
+ */
+export function isFork(t) {
+  return Array.isArray(t) && t.length === 2;
+}
+
+/**
+ * Check if a value is a valid tree calculus value (Leaf, Stem, or Fork).
+ */
+export function isTree(t) {
+  return isLeaf(t) || isStem(t) || isFork(t);
+}
+
+/**
+ * Triage a tree: classify it as Leaf/Stem/Fork.
+ * The tree must be in normal form (no reducible redexes).
+ *
+ * Returns { kind: "leaf"|"stem"|"fork", ...rest }
+ */
+export function triage(t) {
+  if (!Array.isArray(t)) {
+    throw new Error("not a tree (not an array)");
+  }
+  if (t.length === 0) return { kind: "leaf" };
+  if (t.length === 1) return { kind: "stem", child: t[0] };
+  if (t.length === 2) return { kind: "fork", right: t[0], left: t[1] };
+  throw new Error(`not a value/binary tree: length ${t.length}`);
+}
+
+/**
+ * Apply the Tree Calculus apply rules.
+ *
+ * apply(a, b) computes the application of term a to term b.
+ *
+ * Rules:
+ *   apply(Fork(Leaf, a), _)       = a
+ *   apply(Fork(Stem(a), b), c)    = apply(apply(a, c), apply(b, c))
+ *   apply(Fork(Fork, _, _), Leaf) = left of inner Fork
+ *   apply(Fork(Fork, _, _), Stem) = right of inner Fork
+ *   apply(Fork(Fork, _, _), Fork) = apply(apply(c, u), v)  where c=Fork(u,v)
+ *   apply(Leaf, b)               = Stem(b)
+ *   apply(Stem(a), b)            = Fork(a, b)
+ *
+ * For Fork, the inner structure is [right, left], so:
+ *   a = right, b = left
+ */
+export function apply(a, b) {
+  // apply(Fork(Leaf, a), _) = a
+  // Fork = [right, left] = [Leaf, a] → left child is Leaf
+  if (isFork(a) && isLeaf(a[1])) {
+    return a[0]; // return right child
+  }
+
+  // apply(Fork(Stem(a), b), c)
+  if (isFork(a) && isStem(a[1])) {
+    const stemChild = a[1][0]; // left child of fork
+    const right = a[0]; // right child of fork
+    const innerA = stemChild;
+    const innerB = right;
+    const appliedA = apply(innerA, b);
+    const appliedB = apply(innerB, b);
+    return apply(appliedA, appliedB);
+  }
+
+  // apply(Fork(Fork, _, _), Leaf)
+  if (isFork(a) && isFork(a[1]) && isLeaf(b)) {
+    return a[1][0]; // right child of inner fork (which is left child)
+  }
+
+  // apply(Fork(Fork, _, _), Stem)
+  if (isFork(a) && isFork(a[1]) && isStem(b)) {
+    return a[1][1]; // left child of inner fork
+  }
+
+  // apply(Fork(Fork, _, _), Fork)
+  if (isFork(a) && isFork(a[1]) && isFork(b)) {
+    // b = Fork(u, v) = [v, u]
+    const u = b[0];
+    const v = b[1];
+    // apply(apply(c, u), v) where c = inner fork
+    const applied = apply(apply(a[1], u), v);
+    return applied;
+  }
+
+  // apply(Leaf, b) = Stem(b)
+  if (isLeaf(a)) {
+    return [b];
+  }
+
+  // apply(Stem(a), b) = Fork(a, b)
+  if (isStem(a)) {
+    return [b, a[0]]; // [right, left]
+  }
+
+  throw new Error("apply: undefined reduction for terms");
+}

ext/js/test/bundle.test.js

@@ -0,0 +1,134 @@
+import { readFileSync } from "node:fs";
+import { strictEqual, ok, throws } from "node:assert";
+import { createHash } from "node:crypto";
+import { describe, it } from "node:test";
+import {
+  parseBundle,
+  parseManifest,
+} from "../src/bundle.js";
+import {
+  parseNodeSection as bundleParseNodeSection,
+} from "../src/bundle.js";
+import {
+  verifyNodeHashes,
+  parseNodeSection as parseNodes,
+} from "../src/merkle.js";
+
+const fixtureDir = "../../test/fixtures";
+
+describe("bundle parsing", () => {
+  it("valid bundle parses header and sections", () => {
+    const bundle = parseBundle(
+      readFileSync(`${fixtureDir}/id.arboricx`)
+    );
+    strictEqual(bundle.version, "1.0");
+    strictEqual(bundle.sectionCount, 2);
+    ok(bundle.sections.has(1)); // manifest
+    ok(bundle.sections.has(2)); // nodes
+  });
+
+  it("parseManifest returns valid manifest", () => {
+    const manifest = parseManifest(
+      readFileSync(`${fixtureDir}/id.arboricx`)
+    );
+    strictEqual(manifest.schema, "arboricx.bundle.manifest.v1");
+    strictEqual(manifest.bundleType, "tree-calculus-executable-object");
+    strictEqual(manifest.closure, "complete");
+    strictEqual(manifest.tree.calculus, "tree-calculus.v1");
+    strictEqual(manifest.tree.nodeHash.algorithm, "sha256");
+    strictEqual(manifest.tree.nodeHash.domain, "arboricx.merkle.node.v1");
+    strictEqual(manifest.runtime.semantics, "tree-calculus.v1");
+    strictEqual(manifest.runtime.abi, "arboricx.abi.tree.v1");
+  });
+});
+
+describe("hash verification", () => {
+  it("valid bundle nodes verify", () => {
+    const data = bundleParseNodeSection(
+      readFileSync(`${fixtureDir}/id.arboricx`)
+    );
+    const { nodeMap } = parseNodes(data);
+    const { verified } = verifyNodeHashes(nodeMap);
+    ok(verified, "all node hashes should verify");
+  });
+});
+
+describe("errors", () => {
+  it("bad magic fails", () => {
+    const buf = Buffer.alloc(32, 0);
+    buf.write("WRONGMAG", 0, 8);
+    throws(() => parseBundle(buf), /invalid magic/);
+  });
+
+  it("unsupported version fails", () => {
+    const buf = Buffer.alloc(32, 0);
+    buf.write("ARBORICX", 0, 8);
+    buf.writeUInt16BE(2, 8); // major version 2
+    throws(() => parseBundle(buf), /unsupported bundle major version/);
+  });
+
+  it("bad section digest fails", () => {
+    const buf = readFileSync(`${fixtureDir}/id.arboricx`);
+    // Corrupt one byte in the manifest section
+    buf[152] ^= 0x01;
+    throws(() => parseBundle(buf), /digest mismatch/);
+  });
+
+  it("truncated bundle fails", () => {
+    const buf = readFileSync(`${fixtureDir}/id.arboricx`);
+    const truncated = buf.slice(0, 40);
+    throws(() => parseBundle(truncated), /truncated/);
+  });
+
+  it("missing nodes section fails", () => {
+    // Build a bundle with only manifest entry in the directory (1 section instead of 2)
+    const header = Buffer.alloc(32, 0);
+    header.write("ARBORICX", 0, 8);
+    header.writeUInt16BE(1, 8);  // major version
+    header.writeUInt16BE(0, 10); // minor version
+    header.writeUInt32BE(1, 12); // 1 section
+
+    // Build a manifest JSON
+    const manifestObj = {
+      schema: "arboricx.bundle.manifest.v1",
+      bundleType: "tree-calculus-executable-object",
+      tree: {
+        calculus: "tree-calculus.v1",
+        nodeHash: {
+          algorithm: "sha256",
+          domain: "arboricx.merkle.node.v1"
+        },
+        nodePayload: "arboricx.merkle.payload.v1"
+      },
+      runtime: {
+        semantics: "tree-calculus.v1",
+        evaluation: "normal-order",
+        abi: "arboricx.abi.tree.v1",
+        capabilities: []
+      },
+      closure: "complete",
+      roots: [{ hash: Buffer.alloc(32).toString("hex"), role: "default" }],
+      exports: [{ name: "root", root: Buffer.alloc(32).toString("hex"), kind: "term", abi: "arboricx.abi.tree.v1" }],
+      metadata: { createdBy: "arboricx" }
+    };
+    const manifestJson = JSON.stringify(manifestObj);
+    const manifestBytes = Buffer.from(manifestJson);
+
+    // Section directory entry (60 bytes, all fields are u64 after the u16s)
+    const entry = Buffer.alloc(60, 0);
+    entry.writeUInt32BE(1, 0);    // type: manifest
+    entry.writeUInt16BE(1, 4);    // version
+    entry.writeUInt16BE(1, 6);    // flags: critical
+    entry.writeUInt16BE(0, 8);    // compression: none
+    entry.writeUInt16BE(1, 10);   // digest algorithm: sha256
+    entry.writeBigUInt64BE(BigInt(32 + 60), 12); // offset (u64)
+    entry.writeBigUInt64BE(BigInt(manifestBytes.length), 20); // length (u64)
+    entry.set(createHash("sha256").update(manifestBytes).digest(), 28); // digest (32 bytes)
+
+    // Set dirOffset to 32 so parseBundle reads directory from after header
+    header.writeBigUInt64BE(BigInt(32), 24);
+
+    const bundleBuf = Buffer.concat([header, entry, manifestBytes]);
+    throws(() => parseBundle(bundleBuf), /missing required section/);
+  });
+});

ext/js/test/merkle.test.js

@@ -0,0 +1,180 @@
+import { readFileSync } from "node:fs";
+import { strictEqual, ok } from "node:assert";
+import { describe, it } from "node:test";
+import { parseNodeSection as bundleParseNodeSection, parseBundle, parseManifest } from "../src/bundle.js";
+import {
+  verifyNodeHashes,
+  verifyClosure,
+  verifyRootClosure,
+  deserializePayload,
+  computeNodeHash,
+  parseNodeSection,
+} from "../src/merkle.js";
+
+describe("merkle — deserializePayload", () => {
+  it("Leaf (0x00)", () => {
+    const result = deserializePayload(Buffer.from([0x00]));
+    strictEqual(result.type, "leaf");
+  });
+
+  it("Stem (0x01 + 32 bytes)", () => {
+    const childHash = Buffer.alloc(32, 0xab);
+    const payload = Buffer.concat([Buffer.from([0x01]), childHash]);
+    const result = deserializePayload(payload);
+    strictEqual(result.type, "stem");
+    strictEqual(result.childHash, "ab".repeat(32));
+  });
+
+  it("Fork (0x02 + 64 bytes)", () => {
+    const left = Buffer.alloc(32, 0x01);
+    const right = Buffer.alloc(32, 0x02);
+    const payload = Buffer.concat([Buffer.from([0x02]), left, right]);
+    const result = deserializePayload(payload);
+    strictEqual(result.type, "fork");
+    strictEqual(result.leftHash, "01".repeat(32));
+    strictEqual(result.rightHash, "02".repeat(32));
+  });
+
+  it("Leaf with extra bytes fails", () => {
+    throws(() => deserializePayload(Buffer.from([0x00, 0x00])), /invalid leaf/);
+  });
+
+  it("Unknown type fails", () => {
+    throws(() => deserializePayload(Buffer.from([0xff])), /unknown type/);
+  });
+});
+
+describe("merkle — computeNodeHash", () => {
+  it("Leaf hash is correct length", () => {
+    const leaf = { type: "leaf" };
+    const hash = computeNodeHash(leaf);
+    strictEqual(hash.length, 64);
+  });
+
+  it("Leaf hash matches expected Arboricx domain", () => {
+    const leaf = { type: "leaf" };
+    const hash = computeNodeHash(leaf);
+    strictEqual(hash, "92b8a9796dbeafbcd36757535876256392170d137bf36b319d77f11a37112158");
+  });
+});
+
+describe("merkle — node section parsing", () => {
+  const fixtureDir = "../../test/fixtures";
+
+  it("parses id.arboricx with correct node count", () => {
+    const data = bundleParseNodeSection(
+      readFileSync(`${fixtureDir}/id.arboricx`)
+    );
+    const { nodeMap } = parseNodeSection(data);
+    strictEqual(nodeMap.size, 4);
+  });
+
+  it("parses true.arboricx with correct node count", () => {
+    const data = bundleParseNodeSection(
+      readFileSync(`${fixtureDir}/true.arboricx`)
+    );
+    const { nodeMap } = parseNodeSection(data);
+    strictEqual(nodeMap.size, 2);
+  });
+
+  it("parses false.arboricx with correct node count", () => {
+    const data = bundleParseNodeSection(
+      readFileSync(`${fixtureDir}/false.arboricx`)
+    );
+    const { nodeMap } = parseNodeSection(data);
+    strictEqual(nodeMap.size, 1);
+  });
+});
+
+describe("merkle — hash verification", () => {
+  const fixtureDir = "../../test/fixtures";
+
+  it("id.arboricx nodes all verify", () => {
+    const data = bundleParseNodeSection(
+      readFileSync(`${fixtureDir}/id.arboricx`)
+    );
+    const { nodeMap } = parseNodeSection(data);
+    const { verified, mismatches } = verifyNodeHashes(nodeMap);
+    ok(verified, "id.arboricx node hashes should verify");
+    strictEqual(mismatches.length, 0);
+  });
+
+  it("true.arboricx nodes all verify", () => {
+    const data = bundleParseNodeSection(
+      readFileSync(`${fixtureDir}/true.arboricx`)
+    );
+    const { nodeMap } = parseNodeSection(data);
+    const { verified, mismatches } = verifyNodeHashes(nodeMap);
+    ok(verified, "true.arboricx node hashes should verify");
+    strictEqual(mismatches.length, 0);
+  });
+
+  it("corrupted node payload fails hash verification", () => {
+    const data = bundleParseNodeSection(
+      readFileSync(`${fixtureDir}/id.arboricx`)
+    );
+    const { nodeMap } = parseNodeSection(data);
+    // Find a stem node to corrupt
+    let stemKey = null;
+    for (const [key, node] of nodeMap) {
+      if (node.type === "stem") { stemKey = key; break; }
+    }
+    ok(stemKey, "should find a stem node to corrupt");
+    const stem = nodeMap.get(stemKey);
+    // Corrupt the child hash so serializeNode produces a different payload
+    const corrupted = {
+      ...stem,
+      childHash: "00".repeat(32),
+      payload: Buffer.concat([Buffer.from([0x01]), Buffer.alloc(32, 0x00)]),
+    };
+    nodeMap.set(stemKey, corrupted);
+    const { verified, mismatches } = verifyNodeHashes(nodeMap);
+    ok(!verified, "corrupted stem should fail hash verification");
+    ok(mismatches.length > 0, "should have mismatches");
+  });
+});
+
+describe("merkle — closure verification", () => {
+  const fixtureDir = "../../test/fixtures";
+
+  it("id.arboricx has complete closure", () => {
+    const data = bundleParseNodeSection(
+      readFileSync(`${fixtureDir}/id.arboricx`)
+    );
+    const { nodeMap } = parseNodeSection(data);
+    const { complete, missing } = verifyClosure(nodeMap);
+    ok(complete, "id.arboricx should have complete closure");
+    strictEqual(missing.length, 0);
+  });
+
+  it("verifyRootClosure checks transitive reachability", () => {
+    const data = bundleParseNodeSection(
+      readFileSync(`${fixtureDir}/id.arboricx`)
+    );
+    const { nodeMap } = parseNodeSection(data);
+    // Use the actual root hash from the fixture's manifest
+    const manifest = parseManifest(readFileSync(`${fixtureDir}/id.arboricx`));
+    const rootHash = manifest.exports[0].root;
+    const { complete, missingRoots } = verifyRootClosure(nodeMap, rootHash);
+    ok(complete, "root should be reachable");
+    strictEqual(missingRoots.length, 0);
+  });
+
+  it("parseNodeSection returns correct node count", () => {
+    const data = bundleParseNodeSection(
+      readFileSync(`${fixtureDir}/id.arboricx`)
+    );
+    const result = parseNodeSection(data);
+    strictEqual(result.count, 4);
+  });
+});
+
+// Helper for throws
+function throws(fn, expected) {
+  try {
+    fn();
+    return false;
+  } catch (e) {
+    return expected.test(e.message);
+  }
+}

ext/js/test/reduce.test.js

@@ -0,0 +1,80 @@
+import { strictEqual, ok } from "node:assert";
+import { describe, it } from "node:test";
+import { apply, isLeaf, isStem, isFork } from "../src/tree.js";
+import { reduce } from "../src/cli.js";
+
+describe("tree — basic types", () => {
+  it("Leaf is empty array", () => {
+    ok(isLeaf([]));
+    ok(!isStem([]));
+    ok(!isFork([]));
+  });
+
+  it("Stem is single-element array", () => {
+    ok(isStem([[]]));
+    ok(!isLeaf([[]]));
+  });
+
+  it("Fork is two-element array", () => {
+    ok(isFork([[], []]));
+    ok(!isLeaf([[], []]));
+  });
+});
+
+describe("tree — apply rules", () => {
+  // Leaf = [], Stem = [child], Fork = [right, left]
+
+  it("apply(Leaf, b) = Stem(b)", () => {
+    const b = []; // Leaf
+    const result = apply([], b);
+    ok(isStem(result), "Stem(b) should be a Stem");
+    strictEqual(result[0], b);
+  });
+
+  it("apply(Stem(a), b) = Fork(a, b)", () => {
+    const a = []; // Leaf
+    const b = []; // Leaf
+    const result = apply([a], b);
+    ok(isFork(result), "Fork(a, b) should be a Fork");
+    // Fork = [right, left] = [b, a]
+    strictEqual(result[0], b);
+    strictEqual(result[1], a);
+  });
+
+  it("apply(Fork(Leaf, a), _) = a", () => {
+    // Fork(Leaf, a) = [a, Leaf]
+    const a = []; // Leaf
+    const result = apply([a, []], []);
+    strictEqual(result, a);
+    ok(isLeaf(result));
+  });
+});
+
+describe("tree — reduction", () => {
+  it("reduces Leaf to Leaf", () => {
+    const result = reduce([], 100);
+    ok(isLeaf(result));
+  });
+
+  it("reduces Stem Leaf to Stem Leaf", () => {
+    const result = reduce([[]], 100);
+    ok(isStem(result));
+    ok(isLeaf(result[0]));
+  });
+
+  it("reduces Fork Leaf Leaf to Fork Leaf Leaf", () => {
+    const result = reduce([[], []], 100);
+    ok(isFork(result));
+    ok(isLeaf(result[0]));
+    ok(isLeaf(result[1]));
+  });
+
+  it("S combinator applied to Leaf reduces", () => {
+    // S = t (t (t t)) t = Fork (Fork (Fork Leaf Leaf) Leaf) Leaf
+    // In array form: [[[], []], [], []]
+    const s = [[], [[[], []], []]];
+    const leaf = [];
+    const result = reduce([s, leaf], 100);
+    ok(Array.isArray(result), "S Leaf should reduce to an array");
+  });
+});

ext/js/test/run-bundle.test.js

@@ -0,0 +1,120 @@
+import { readFileSync } from "node:fs";
+import { strictEqual, ok, throws } from "node:assert";
+import { describe, it } from "node:test";
+import { parseManifest } from "../src/bundle.js";
+import { parseNodeSection as bundleParseNodeSection } from "../src/bundle.js";
+import { validateManifest, selectExport } from "../src/manifest.js";
+import { verifyNodeHashes, parseNodeSection as parseNodes } from "../src/merkle.js";
+import { buildTreeFromNodeMap } from "../src/cli.js";
+
+const fixtureDir = "../../test/fixtures";
+
+describe("run bundle — id.arboricx", () => {
+  const bundle = readFileSync(`${fixtureDir}/id.arboricx`);
+  const manifest = parseManifest(bundle);
+  const nodeSectionData = bundleParseNodeSection(bundle);
+  const { nodeMap } = parseNodes(nodeSectionData);
+
+  it("manifest validates", () => {
+    validateManifest(manifest);
+  });
+
+  it("node hashes verify", () => {
+    const { verified } = verifyNodeHashes(nodeMap);
+    ok(verified);
+  });
+
+  it("export 'root' is selectable", () => {
+    const exp = selectExport(manifest, "root");
+    strictEqual(exp.name, "root");
+  });
+
+  it("tree reconstructs as a Fork", () => {
+    const exp = selectExport(manifest, "root");
+    const tree = buildTreeFromNodeMap(nodeMap, exp.root);
+    ok(Array.isArray(tree));
+    ok(tree.length >= 2, "tree should be a Fork (length >= 2)");
+  });
+});
+
+describe("run bundle — true.arboricx", () => {
+  const bundle = readFileSync(`${fixtureDir}/true.arboricx`);
+  const manifest = parseManifest(bundle);
+  const nodeSectionData = bundleParseNodeSection(bundle);
+  const { nodeMap } = parseNodes(nodeSectionData);
+
+  it("manifest validates", () => {
+    validateManifest(manifest);
+  });
+
+  it("export 'root' is selectable", () => {
+    const exp = selectExport(manifest, "root");
+    strictEqual(exp.name, "root");
+  });
+
+  it("tree reconstructs as Stem Leaf", () => {
+    const exp = selectExport(manifest, "root");
+    const tree = buildTreeFromNodeMap(nodeMap, exp.root);
+    ok(Array.isArray(tree));
+    strictEqual(tree.length, 1, "true should be a Stem (single child)");
+    strictEqual(tree[0].length, 0, "child should be Leaf");
+  });
+});
+
+describe("run bundle — false.arboricx", () => {
+  const bundle = readFileSync(`${fixtureDir}/false.arboricx`);
+  const manifest = parseManifest(bundle);
+  const nodeSectionData = bundleParseNodeSection(bundle);
+  const { nodeMap } = parseNodes(nodeSectionData);
+
+  it("manifest validates", () => {
+    validateManifest(manifest);
+  });
+
+  it("export 'root' is selectable", () => {
+    const exp = selectExport(manifest, "root");
+    strictEqual(exp.name, "root");
+  });
+
+  it("tree reconstructs as Leaf", () => {
+    const exp = selectExport(manifest, "root");
+    const tree = buildTreeFromNodeMap(nodeMap, exp.root);
+    strictEqual(tree.length, 0, "false should be Leaf (empty array)");
+  });
+});
+
+describe("run bundle — notQ.arboricx", () => {
+  const bundle = readFileSync(`${fixtureDir}/notQ.arboricx`);
+  const manifest = parseManifest(bundle);
+  const nodeSectionData = bundleParseNodeSection(bundle);
+  const { nodeMap } = parseNodes(nodeSectionData);
+
+  it("manifest validates", () => {
+    validateManifest(manifest);
+  });
+
+  it("node hashes verify", () => {
+    const { verified } = verifyNodeHashes(nodeMap);
+    ok(verified);
+  });
+});
+
+describe("run bundle — missing export", () => {
+  const bundle = readFileSync(`${fixtureDir}/id.arboricx`);
+  const manifest = parseManifest(bundle);
+
+  it("nonexistent export fails clearly", () => {
+    throws(() => selectExport(manifest, "nonexistent"), /not found/);
+  });
+});
+
+describe("run bundle — auto-select", () => {
+  // true.arboricx has only one export, should auto-select
+  const bundle = readFileSync(`${fixtureDir}/true.arboricx`);
+  const manifest = parseManifest(bundle);
+
+  it("single export auto-selects", () => {
+    const exp = selectExport(manifest, undefined);
+    ok(exp, "should auto-select the only export");
+  });
+});

ext/php/run.php

@@ -0,0 +1,172 @@
+#!/usr/bin/env php
+<?php
+
+declare(strict_types=1);
+
+/**
+ * run.php — Arboricx PHP host shell via libarboricx C ABI.
+ *
+ * Usage:
+ *   php run.php run <bundle.arboricx> [args...]
+ *   php run.php inspect <bundle.arboricx>
+ */
+
+require __DIR__ . '/src/ffi.php';
+
+use function Arboricx\{ctx_init, ctx_free, loadBundleDefault, ofNumber, ofString, app, reduce, toString, toBool, toNumber};
+
+// ── Locate libarboricx.so ──────────────────────────────────────────────────
+
+function findLib(): string
+{
+    $env = getenv('ARBORICX_LIB');
+    if ($env !== false && file_exists($env)) {
+        return $env;
+    }
+
+    $paths = [
+        __DIR__ . '/../../zig/zig-out/lib/libarboricx.so',
+        '/usr/local/lib/libarboricx.so',
+        '/usr/lib/libarboricx.so',
+        './libarboricx.so',
+    ];
+    foreach ($paths as $p) {
+        if (file_exists($p)) {
+            return $p;
+        }
+    }
+
+    fwrite(STDERR, "Error: libarboricx.so not found.\nSet ARBORICX_LIB to its full path.\n");
+    exit(1);
+}
+
+// ── Decode helpers ─────────────────────────────────────────────────────────
+
+function decode(\FFI\CData $ctx, int $root): string
+{
+    // Bool first: false is Leaf, which is also a valid empty string/list.
+    try {
+        return toBool($ctx, $root) ? 'true' : 'false';
+    } catch (\Throwable $e) {
+        try {
+            return toString($ctx, $root);
+        } catch (\Throwable $e2) {
+            try {
+                return (string) toNumber($ctx, $root);
+            } catch (\Throwable $e3) {
+                throw new \RuntimeException('could not decode result');
+            }
+        }
+    }
+}
+
+function decodeType(\FFI\CData $ctx, int $root): string
+{
+    try {
+        toBool($ctx, $root);
+        return 'bool';
+    } catch (\Throwable $e) {
+        try {
+            toString($ctx, $root);
+            return 'string';
+        } catch (\Throwable $e2) {
+            try {
+                toNumber($ctx, $root);
+                return 'number';
+            } catch (\Throwable $e3) {
+                return 'unknown (raw tree)';
+            }
+        }
+    }
+}
+
+// ── Commands ─────────────────────────────────────────────────────────────────
+
+function readBundle(string $path): string
+{
+    if (!file_exists($path)) {
+        fwrite(STDERR, "Error: bundle not found: $path\n");
+        exit(1);
+    }
+    $bytes = file_get_contents($path);
+    if ($bytes === false) {
+        fwrite(STDERR, "Error: could not read bundle: $path\n");
+        exit(1);
+    }
+    return $bytes;
+}
+
+function cmdRun(string $libPath, string $bundlePath, array $args): void
+{
+    $ctx = ctx_init($libPath);
+    try {
+        $term = loadBundleDefault($ctx, readBundle($bundlePath));
+
+        foreach ($args as $arg) {
+            $argTree = preg_match('/^\d+$/', $arg) ? ofNumber($ctx, (int)$arg) : ofString($ctx, $arg);
+            $term = app($ctx, $term, $argTree);
+        }
+
+        $result = reduce($ctx, $term, 1_000_000_000);
+        echo decode($ctx, $result) . "\n";
+    } finally {
+        ctx_free($ctx);
+    }
+}
+
+function cmdInspect(string $libPath, string $bundlePath): void
+{
+    $ctx = ctx_init($libPath);
+    try {
+        $bundle = readBundle($bundlePath);
+        echo "Bundle: $bundlePath\nSize: " . strlen($bundle) . " bytes\n\nResult:\n";
+
+        $term = loadBundleDefault($ctx, $bundle);
+        $result = reduce($ctx, $term, 1_000_000_000);
+
+        $type = decodeType($ctx, $result);
+        try {
+            $value = decode($ctx, $result);
+        } catch (\RuntimeException $e) {
+            $value = '(raw tree)';
+        }
+        echo "  Type: $type\n  Value: $value\n";
+    } finally {
+        ctx_free($ctx);
+    }
+}
+
+// ── Main ─────────────────────────────────────────────────────────────────────
+
+$argv = $_SERVER['argv'] ?? [];
+$argc = $_SERVER['argc'] ?? 0;
+
+if ($argc < 2) {
+    echo "Arboricx PHP Host Shell (via libarboricx C ABI)\n\nUsage:\n";
+    echo "  php run.php run <bundle.arboricx> [args...]\n";
+    echo "  php run.php inspect <bundle.arboricx>\n";
+    exit(0);
+}
+
+$libPath = findLib();
+$command = $argv[1];
+
+switch ($command) {
+    case 'run':
+        if ($argc < 3) {
+            fwrite(STDERR, "Usage: php run.php run <bundle.arboricx> [args...]\n");
+            exit(1);
+        }
+        cmdRun($libPath, $argv[2], array_slice($argv, 3));
+        break;
+    case 'inspect':
+        if ($argc < 3) {
+            fwrite(STDERR, "Usage: php run.php inspect <bundle.arboricx>\n");
+            exit(1);
+        }
+        cmdInspect($libPath, $argv[2]);
+        break;
+    default:
+        fwrite(STDERR, "Unknown command: $command\nUsage: php run.php run|inspect ...\n");
+        exit(1);
+}

ext/php/src/ffi.php

@@ -0,0 +1,138 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Arboricx;
+
+/**
+ * FFI wrapper around libarboricx.so.
+ *
+ * Loads the shared library and exposes typed wrappers for the C ABI.
+ */
+final class ArboricxFFI
+{
+    private static ?\FFI $ffi = null;
+
+    public static function init(string $libPath): void
+    {
+        if (self::$ffi !== null) {
+            return;
+        }
+
+        // Nix output layout first, then repo layout.
+        $candidates = [
+            __DIR__ . '/../arboricx.h',
+            __DIR__ . '/../../zig/include/arboricx.h',
+        ];
+        $headerRaw = false;
+        foreach ($candidates as $path) {
+            $headerRaw = file_get_contents($path);
+            if ($headerRaw !== false) break;
+        }
+        if ($headerRaw === false) {
+            throw new \RuntimeException('Cannot read arboricx.h');
+        }
+
+        // PHP FFI only parses plain C declarations.
+        $header = $headerRaw;
+        $header = preg_replace('/#.*\n/', "\n", $header);
+        $header = preg_replace('/extern\s+"C"\s*\{/', '', $header);
+        $header = str_replace('}', '', $header);
+        $header = preg_replace('/\n\s*\n+/', "\n", $header);
+
+        self::$ffi = \FFI::cdef($header, $libPath);
+    }
+
+    public static function ffi(): \FFI
+    {
+        if (self::$ffi === null) {
+            throw new \RuntimeException('ArboricxFFI not initialized. Call ArboricxFFI::init($libPath) first.');
+        }
+        return self::$ffi;
+    }
+}
+
+function ctx_init(string $libPath): \FFI\CData
+{
+    ArboricxFFI::init($libPath);
+    $ctx = ArboricxFFI::ffi()->arboricx_init();
+    if ($ctx === null) {
+        throw new \RuntimeException('arboricx_init failed');
+    }
+    return $ctx;
+}
+
+function ctx_free(\FFI\CData $ctx): void
+{
+    ArboricxFFI::ffi()->arboricx_free($ctx);
+}
+
+function app(\FFI\CData $ctx, int $func, int $arg): int
+{
+    return ArboricxFFI::ffi()->arb_app($ctx, $func, $arg);
+}
+
+function reduce(\FFI\CData $ctx, int $root, int $fuel = 1_000_000_000): int
+{
+    return ArboricxFFI::ffi()->arb_reduce($ctx, $root, $fuel);
+}
+
+function ofNumber(\FFI\CData $ctx, int $n): int
+{
+    return ArboricxFFI::ffi()->arb_of_number($ctx, $n);
+}
+
+function ofString(\FFI\CData $ctx, string $s): int
+{
+    return ArboricxFFI::ffi()->arb_of_string($ctx, $s);
+}
+
+function toNumber(\FFI\CData $ctx, int $root): int
+{
+    $out = ArboricxFFI::ffi()->new('uint64_t');
+    $ok = ArboricxFFI::ffi()->arb_to_number($ctx, $root, \FFI::addr($out));
+    if (!$ok) {
+        throw new \RuntimeException('arb_to_number failed');
+    }
+    return (int) $out->cdata;
+}
+
+function toString(\FFI\CData $ctx, int $root): string
+{
+    $ptr = ArboricxFFI::ffi()->new('uint8_t*');
+    $len = ArboricxFFI::ffi()->new('size_t');
+    $ok = ArboricxFFI::ffi()->arb_to_string($ctx, $root, \FFI::addr($ptr), \FFI::addr($len));
+    if (!$ok) {
+        throw new \RuntimeException('arb_to_string failed');
+    }
+    $length = (int) $len->cdata;
+    $result = '';
+    for ($i = 0; $i < $length; $i++) {
+        $result .= chr($ptr[$i]);
+    }
+    ArboricxFFI::ffi()->arboricx_free_buf($ctx, $ptr, $length);
+    return $result;
+}
+
+function toBool(\FFI\CData $ctx, int $root): bool
+{
+    $out = ArboricxFFI::ffi()->new('int');
+    $ok = ArboricxFFI::ffi()->arb_to_bool($ctx, $root, \FFI::addr($out));
+    if (!$ok) {
+        throw new \RuntimeException('arb_to_bool failed');
+    }
+    return (bool) $out->cdata;
+}
+
+function loadBundleDefault(\FFI\CData $ctx, string $bytes): int
+{
+    $cdata = ArboricxFFI::ffi()->new('uint8_t[' . strlen($bytes) . ']');
+    for ($i = 0; $i < strlen($bytes); $i++) {
+        $cdata[$i] = ord($bytes[$i]);
+    }
+    $result = ArboricxFFI::ffi()->arb_load_bundle_default($ctx, $cdata, strlen($bytes));
+    if ($result === 0) {
+        throw new \RuntimeException('arb_load_bundle_default failed');
+    }
+    return $result;
+}

ext/zig/.gitignore

@@ -0,0 +1,13 @@
+# Zig build artifacts
+.zig-cache/
+zig-out/
+
+# Generated binaries (keep .c sources, ignore compiled artifacts)
+/c_abi_test
+/c_abi_append_test
+c_abi_append_shared
+tests/c_abi_append_test
+
+# Temp files
+*.o
+*.tmp

ext/zig/build.zig

@@ -0,0 +1,67 @@
+const std = @import("std");
+
+pub fn build(b: *std.Build) void {
+    const target = b.standardTargetOptions(.{});
+    const optimize = b.standardOptimizeOption(.{});
+
+    // -- kernel generator tool (runs on build host) --
+    const gen_kernel_mod = b.createModule(.{
+        .root_source_file = b.path("tools/gen_kernel.zig"),
+        .target = b.graph.host,
+        .optimize = .ReleaseSafe,
+    });
+    const gen_kernel = b.addExecutable(.{
+        .name = "gen_kernel",
+        .root_module = gen_kernel_mod,
+    });
+
+    const run_gen_kernel = b.addRunArtifact(gen_kernel);
+    run_gen_kernel.addFileArg(b.path("kernel_run_arboricx_typed.dag"));
+    const kernel_embed = run_gen_kernel.addOutputFileArg("kernel_embed.zig");
+
+    // -- kernel module shared by exe and lib --
+    const kernel_mod = b.createModule(.{
+        .root_source_file = kernel_embed,
+    });
+
+    // -- main CLI executable --
+    const exe_mod = b.createModule(.{
+        .root_source_file = b.path("src/main.zig"),
+        .target = target,
+        .optimize = optimize,
+    });
+    exe_mod.addImport("kernel_embed", kernel_mod);
+    const exe = b.addExecutable(.{
+        .name = "tricu-zig",
+        .root_module = exe_mod,
+    });
+    b.installArtifact(exe);
+
+    const run_cmd = b.addRunArtifact(exe);
+    run_cmd.step.dependOn(b.getInstallStep());
+    const run_step = b.step("run", "Run tricu-zig");
+    run_step.dependOn(&run_cmd.step);
+
+    // -- C ABI static library --
+    const lib_mod = b.createModule(.{
+        .root_source_file = b.path("src/c_abi.zig"),
+        .target = target,
+        .optimize = optimize,
+    });
+    lib_mod.pic = true;
+    lib_mod.addImport("kernel_embed", kernel_mod);
+    const static_lib = b.addLibrary(.{
+        .name = "arboricx",
+        .root_module = lib_mod,
+    });
+    b.installArtifact(static_lib);
+
+    // -- C ABI shared library (for dynamic language FFI) --
+    const shared_lib = b.addLibrary(.{
+        .name = "arboricx",
+        .root_module = lib_mod,
+        .linkage = .dynamic,
+    });
+    b.installArtifact(shared_lib);
+
+}

ext/zig/build.zig.zon

@@ -0,0 +1,13 @@
+.{
+    .name = .tricu_zig,
+    .version = "0.0.1",
+    .fingerprint = 0xa9aedd8049d1cce9,
+    .minimum_zig_version = "0.16.0",
+    .paths = .{
+        "build.zig",
+        "build.zig.zon",
+        "src",
+        "tools",
+        "kernels",
+    },
+}

ext/zig/include/arboricx.h

@@ -0,0 +1,54 @@
+#ifndef ARBORICX_H
+#define ARBORICX_H
+
+#include <stddef.h>
+#include <stdint.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef struct arb_ctx arb_ctx_t;
+
+/* Context lifecycle */
+arb_ctx_t* arboricx_init(void);
+void arboricx_free(arb_ctx_t* ctx);
+void arboricx_free_buf(arb_ctx_t* ctx, uint8_t* ptr, size_t len);
+
+/* Tree construction */
+uint32_t arb_leaf(arb_ctx_t* ctx);
+uint32_t arb_stem(arb_ctx_t* ctx, uint32_t child);
+uint32_t arb_fork(arb_ctx_t* ctx, uint32_t left, uint32_t right);
+uint32_t arb_app(arb_ctx_t* ctx, uint32_t func, uint32_t arg);
+
+/* Reduction */
+uint32_t arb_reduce(arb_ctx_t* ctx, uint32_t root, uint64_t fuel);
+
+/* Codec constructors */
+uint32_t arb_of_number(arb_ctx_t* ctx, uint64_t n);
+uint32_t arb_of_string(arb_ctx_t* ctx, const char* s);
+uint32_t arb_of_bytes(arb_ctx_t* ctx, const uint8_t* bytes, size_t len);
+uint32_t arb_of_list(arb_ctx_t* ctx, const uint32_t* items, size_t len);
+
+/* Codec destructors (return 1 on success, 0 on failure) */
+int arb_to_number(arb_ctx_t* ctx, uint32_t root, uint64_t* out);
+int arb_to_string(arb_ctx_t* ctx, uint32_t root, uint8_t** out_ptr, size_t* out_len);
+int arb_to_bytes(arb_ctx_t* ctx, uint32_t root, uint8_t** out_ptr, size_t* out_len);
+int arb_to_bool(arb_ctx_t* ctx, uint32_t root, int* out);
+
+/* Result unwrapping (return 1 on success, 0 on failure) */
+int arb_unwrap_result(arb_ctx_t* ctx, uint32_t root, int* out_ok, uint32_t* out_value, uint32_t* out_rest);
+int arb_unwrap_host_value(arb_ctx_t* ctx, uint32_t root, uint64_t* out_tag, uint32_t* out_payload);
+
+/* Kernel entrypoints */
+uint32_t arb_kernel_root(arb_ctx_t* ctx);
+
+/* Native bundle loading (fast path — bypasses the Tricu kernel) */
+uint32_t arb_load_bundle(arb_ctx_t* ctx, const uint8_t* bytes, size_t len, const char* name);
+uint32_t arb_load_bundle_default(arb_ctx_t* ctx, const uint8_t* bytes, size_t len);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* ARBORICX_H */

ext/zig/src/arena.zig

@@ -0,0 +1,36 @@
+const std = @import("std");
+const tree = @import("tree.zig");
+
+pub const Arena = struct {
+    allocator: std.mem.Allocator,
+    nodes: std.ArrayList(tree.Node),
+
+    pub fn init(allocator: std.mem.Allocator) Arena {
+        return .{
+            .allocator = allocator,
+            .nodes = .empty,
+        };
+    }
+
+    pub fn deinit(self: *Arena) void {
+        self.nodes.deinit(self.allocator);
+    }
+
+    pub fn alloc(self: *Arena, node: tree.Node) !u32 {
+        const idx: u32 = @intCast(self.nodes.items.len);
+        try self.nodes.append(self.allocator, node);
+        return idx;
+    }
+
+    pub fn get(self: *Arena, idx: u32) *tree.Node {
+        return &self.nodes.items[idx];
+    }
+
+    pub fn len(self: *const Arena) u32 {
+        return @intCast(self.nodes.items.len);
+    }
+
+    pub fn reset(self: *Arena, keep: u32) void {
+        self.nodes.shrinkRetainingCapacity(keep);
+    }
+};

ext/zig/src/bundle.zig

@@ -0,0 +1,479 @@
+const std = @import("std");
+const tree = @import("tree.zig");
+const Arena = @import("arena.zig").Arena;
+
+pub const Hash = [32]u8;
+
+pub const Error = error{
+    InvalidMagic,
+    InvalidVersion,
+    Truncated,
+    InvalidManifest,
+    InvalidNodePayload,
+    HashMismatch,
+    ExportNotFound,
+    MissingChild,
+    UnexpectedFormat,
+    DigestMismatch,
+    OutOfMemory,
+};
+
+const Parser = struct {
+    bytes: []const u8,
+    pos: usize,
+
+    fn init(bytes: []const u8) Parser {
+        return .{ .bytes = bytes, .pos = 0 };
+    }
+
+    fn remaining(self: *const Parser) usize {
+        return self.bytes.len - self.pos;
+    }
+
+    fn expect(self: *Parser, n: usize) Error![]const u8 {
+        if (self.remaining() < n) return error.Truncated;
+        const result = self.bytes[self.pos .. self.pos + n];
+        self.pos += n;
+        return result;
+    }
+
+    fn readU8(self: *Parser) Error!u8 {
+        const b = try self.expect(1);
+        return b[0];
+    }
+
+    fn readU16(self: *Parser) Error!u16 {
+        const b = try self.expect(2);
+        return std.mem.readInt(u16, b[0..2], .big);
+    }
+
+    fn readU32(self: *Parser) Error!u32 {
+        const b = try self.expect(4);
+        return std.mem.readInt(u32, b[0..4], .big);
+    }
+
+    fn readU64(self: *Parser) Error!u64 {
+        const b = try self.expect(8);
+        return std.mem.readInt(u64, b[0..8], .big);
+    }
+
+    fn readHash(self: *Parser) Error!Hash {
+        const b = try self.expect(32);
+        var h: Hash = undefined;
+        @memcpy(&h, b);
+        return h;
+    }
+
+    fn readLengthPrefixedBytes(self: *Parser, allocator: std.mem.Allocator) Error![]const u8 {
+        const len = try self.readU32();
+        const bytes = try self.expect(len);
+        const copy = try allocator.alloc(u8, bytes.len);
+        @memcpy(copy, bytes);
+        return copy;
+    }
+};
+
+const SectionEntry = struct {
+    section_type: u32,
+    offset: u64,
+    length: u64,
+    digest: Hash,
+};
+
+fn parseHeader(p: *Parser) Error!struct { major: u16, minor: u16, section_count: u32, dir_offset: u64 } {
+    const magic = try p.expect(8);
+    if (!std.mem.eql(u8, magic, "ARBORICX")) return error.InvalidMagic;
+
+    const major = try p.readU16();
+    const minor = try p.readU16();
+    const section_count = try p.readU32();
+    _ = try p.readU64(); // flags
+    const dir_offset = try p.readU64();
+
+    if (major != 1) return error.InvalidVersion;
+
+    return .{ .major = major, .minor = minor, .section_count = section_count, .dir_offset = dir_offset };
+}
+
+fn parseSectionEntries(p: *Parser, count: u32, allocator: std.mem.Allocator) Error![]SectionEntry {
+    const entries = try allocator.alloc(SectionEntry, count);
+    errdefer allocator.free(entries);
+
+    for (entries) |*entry| {
+        entry.section_type = try p.readU32();
+        _ = try p.readU16(); // section_version
+        _ = try p.readU16(); // section_flags
+        const compression = try p.readU16();
+        const digest_alg = try p.readU16();
+        entry.offset = try p.readU64();
+        entry.length = try p.readU64();
+        entry.digest = try p.readHash();
+
+        if (compression != 0) return error.UnexpectedFormat;
+        if (digest_alg != 1) return error.UnexpectedFormat;
+    }
+    return entries;
+}
+
+fn sha256Digest(data: []const u8) Hash {
+    var h = std.crypto.hash.sha2.Sha256.init(.{});
+    h.update(data);
+    var out: Hash = undefined;
+    h.final(&out);
+    return out;
+}
+
+fn parseManifest(p: *Parser, allocator: std.mem.Allocator) Error!struct { exports: []Export, roots: []Root } {
+    const magic = try p.expect(8);
+    if (!std.mem.eql(u8, magic, "ARBMNFST")) return error.InvalidManifest;
+
+    const major = try p.readU16();
+    _ = try p.readU16(); // minor
+    if (major != 1) return error.InvalidVersion;
+
+    const schema = try p.readLengthPrefixedBytes(allocator);
+    defer allocator.free(schema);
+    if (!std.mem.eql(u8, schema, "arboricx.bundle.manifest.v1")) return error.UnexpectedFormat;
+
+    const bundle_type = try p.readLengthPrefixedBytes(allocator);
+    defer allocator.free(bundle_type);
+    if (!std.mem.eql(u8, bundle_type, "tree-calculus-executable-object")) return error.UnexpectedFormat;
+
+    const calc = try p.readLengthPrefixedBytes(allocator);
+    defer allocator.free(calc);
+    if (!std.mem.eql(u8, calc, "tree-calculus.v1")) return error.UnexpectedFormat;
+
+    const hash_alg = try p.readLengthPrefixedBytes(allocator);
+    defer allocator.free(hash_alg);
+    if (!std.mem.eql(u8, hash_alg, "sha256")) return error.UnexpectedFormat;
+
+    const hash_domain = try p.readLengthPrefixedBytes(allocator);
+    defer allocator.free(hash_domain);
+    if (!std.mem.eql(u8, hash_domain, "arboricx.merkle.node.v1")) return error.UnexpectedFormat;
+
+    const payload_type = try p.readLengthPrefixedBytes(allocator);
+    defer allocator.free(payload_type);
+    if (!std.mem.eql(u8, payload_type, "arboricx.merkle.payload.v1")) return error.UnexpectedFormat;
+
+    const sem = try p.readLengthPrefixedBytes(allocator);
+    defer allocator.free(sem);
+    if (!std.mem.eql(u8, sem, "tree-calculus.v1")) return error.UnexpectedFormat;
+
+    const eval_mode = try p.readLengthPrefixedBytes(allocator);
+    defer allocator.free(eval_mode);
+    if (!std.mem.eql(u8, eval_mode, "normal-order")) return error.UnexpectedFormat;
+
+    const abi = try p.readLengthPrefixedBytes(allocator);
+    defer allocator.free(abi);
+    if (!std.mem.eql(u8, abi, "arboricx.abi.tree.v1")) return error.UnexpectedFormat;
+
+    const cap_count = try p.readU32();
+    var i: u32 = 0;
+    while (i < cap_count) : (i += 1) {
+        const cap = try p.readLengthPrefixedBytes(allocator);
+        defer allocator.free(cap);
+        if (cap.len != 0) return error.UnexpectedFormat;
+    }
+
+    const closure = try p.readU8();
+    if (closure != 0) return error.UnexpectedFormat;
+
+    const root_count = try p.readU32();
+    const roots = try allocator.alloc(Root, root_count);
+    errdefer allocator.free(roots);
+    for (roots) |*r| {
+        r.hash = try p.readHash();
+        r.role = try p.readLengthPrefixedBytes(allocator);
+    }
+
+    const export_count = try p.readU32();
+    const exports = try allocator.alloc(Export, export_count);
+    errdefer {
+        for (exports) |*e| {
+            allocator.free(e.name);
+            allocator.free(e.kind);
+            allocator.free(e.abi);
+        }
+        allocator.free(exports);
+    }
+    for (exports) |*e| {
+        e.name = try p.readLengthPrefixedBytes(allocator);
+        e.root = try p.readHash();
+        e.kind = try p.readLengthPrefixedBytes(allocator);
+        e.abi = try p.readLengthPrefixedBytes(allocator);
+        if (!std.mem.eql(u8, e.abi, "arboricx.abi.tree.v1")) return error.UnexpectedFormat;
+    }
+
+    const metadata_count = try p.readU32();
+    var m: u32 = 0;
+    while (m < metadata_count) : (m += 1) {
+        _ = try p.readU16(); // tag
+        const len = try p.readU32();
+        _ = try p.expect(len);
+    }
+
+    const ext_count = try p.readU32();
+    var e_idx: u32 = 0;
+    while (e_idx < ext_count) : (e_idx += 1) {
+        _ = try p.readU16(); // tag
+        const len = try p.readU32();
+        _ = try p.expect(len);
+    }
+
+    return .{ .exports = exports, .roots = roots };
+}
+
+const Export = struct {
+    name: []const u8,
+    root: Hash,
+    kind: []const u8,
+    abi: []const u8,
+};
+
+const Root = struct {
+    hash: Hash,
+    role: []const u8,
+};
+
+fn parseNodeSection(p: *Parser, allocator: std.mem.Allocator) Error!std.AutoHashMap(Hash, []const u8) {
+    const node_count = try p.readU64();
+    var map = std.AutoHashMap(Hash, []const u8).init(allocator);
+    errdefer map.deinit();
+
+    var i: u64 = 0;
+    while (i < node_count) : (i += 1) {
+        const hash = try p.readHash();
+        const plen = try p.readU32();
+        const payload = try p.expect(plen);
+
+        const expected_hash = blk: {
+            var h = std.crypto.hash.sha2.Sha256.init(.{});
+            h.update("arboricx.merkle.node.v1");
+            h.update(&[_]u8{0});
+            h.update(payload);
+            var out: Hash = undefined;
+            h.final(&out);
+            break :blk out;
+        };
+        if (!std.mem.eql(u8, &hash, &expected_hash)) return error.HashMismatch;
+
+        try map.put(hash, payload);
+    }
+
+    return map;
+}
+
+fn loadNode(
+    arena: *Arena,
+    payloads: std.AutoHashMap(Hash, []const u8),
+    cache: *std.AutoHashMap(Hash, u32),
+    root_hash: Hash,
+) Error!u32 {
+    const Frame = struct {
+        hash: Hash,
+        state: u2,
+    };
+
+    const max_stack = payloads.count() * 2;
+    var stack = try arena.allocator.alloc(Frame, max_stack);
+    defer arena.allocator.free(stack);
+    var sp: usize = 0;
+
+    stack[sp] = .{ .hash = root_hash, .state = 0 };
+    sp += 1;
+
+    while (sp > 0) {
+        const frame = &stack[sp - 1];
+
+        if (cache.get(frame.hash)) |_| {
+            sp -= 1;
+            continue;
+        }
+
+        if (frame.state == 0) {
+            frame.state = 1;
+            const payload = payloads.get(frame.hash) orelse return error.MissingChild;
+            if (payload.len == 0) return error.InvalidNodePayload;
+
+            switch (payload[0]) {
+                0x00 => {
+                    if (payload.len != 1) return error.InvalidNodePayload;
+                },
+                0x01 => {
+                    if (payload.len != 33) return error.InvalidNodePayload;
+                    var child_hash: Hash = undefined;
+                    @memcpy(&child_hash, payload[1..33]);
+                    if (cache.get(child_hash) == null) {
+                        stack[sp] = .{ .hash = child_hash, .state = 0 };
+                        sp += 1;
+                    }
+                },
+                0x02 => {
+                    if (payload.len != 65) return error.InvalidNodePayload;
+                    var left_hash: Hash = undefined;
+                    var right_hash: Hash = undefined;
+                    @memcpy(&left_hash, payload[1..33]);
+                    @memcpy(&right_hash, payload[33..65]);
+                    const need_right = cache.get(right_hash) == null;
+                    const need_left = cache.get(left_hash) == null;
+                    if (need_right) {
+                        stack[sp] = .{ .hash = right_hash, .state = 0 };
+                        sp += 1;
+                    }
+                    if (need_left) {
+                        stack[sp] = .{ .hash = left_hash, .state = 0 };
+                        sp += 1;
+                    }
+                },
+                else => return error.InvalidNodePayload,
+            }
+        } else {
+            const payload = payloads.get(frame.hash).?;
+            const idx: u32 = switch (payload[0]) {
+                0x00 => try arena.alloc(.leaf),
+                0x01 => blk: {
+                    var child_hash: Hash = undefined;
+                    @memcpy(&child_hash, payload[1..33]);
+                    const child_idx = cache.get(child_hash).?;
+                    break :blk try arena.alloc(.{ .stem = .{ .child = child_idx } });
+                },
+                0x02 => blk: {
+                    var left_hash: Hash = undefined;
+                    var right_hash: Hash = undefined;
+                    @memcpy(&left_hash, payload[1..33]);
+                    @memcpy(&right_hash, payload[33..65]);
+                    const left_idx = cache.get(left_hash).?;
+                    const right_idx = cache.get(right_hash).?;
+                    break :blk try arena.alloc(.{ .fork = .{ .left = left_idx, .right = right_idx } });
+                },
+                else => unreachable,
+            };
+            try cache.put(frame.hash, idx);
+            sp -= 1;
+        }
+    }
+
+    return cache.get(root_hash) orelse return error.MissingChild;
+}
+
+/// Parse an Arboricx bundle and load the named export into the arena.
+/// Returns the arena index of the exported term tree.
+pub fn loadBundleExport(
+    arena: *Arena,
+    bundle_bytes: []const u8,
+    export_name: []const u8,
+) Error!u32 {
+    var p = Parser.init(bundle_bytes);
+
+    const header = try parseHeader(&p);
+
+    p.pos = @intCast(header.dir_offset);
+    const allocator = arena.allocator;
+    const entries = try parseSectionEntries(&p, header.section_count, allocator);
+    defer allocator.free(entries);
+
+    var manifest_entry: ?SectionEntry = null;
+    var nodes_entry: ?SectionEntry = null;
+    for (entries) |entry| {
+        if (entry.section_type == 1) manifest_entry = entry;
+        if (entry.section_type == 2) nodes_entry = entry;
+    }
+    const manifest_section = manifest_entry orelse return error.InvalidManifest;
+    const nodes_section = nodes_entry orelse return error.InvalidNodePayload;
+
+    const manifest_bytes = bundle_bytes[@intCast(manifest_section.offset)..@intCast(manifest_section.offset + manifest_section.length)];
+    if (!std.mem.eql(u8, &sha256Digest(manifest_bytes), &manifest_section.digest)) return error.DigestMismatch;
+
+    const nodes_bytes = bundle_bytes[@intCast(nodes_section.offset)..@intCast(nodes_section.offset + nodes_section.length)];
+    if (!std.mem.eql(u8, &sha256Digest(nodes_bytes), &nodes_section.digest)) return error.DigestMismatch;
+
+    var mp = Parser.init(manifest_bytes);
+    const manifest = try parseManifest(&mp, allocator);
+    defer {
+        for (manifest.exports) |e| {
+            allocator.free(e.name);
+            allocator.free(e.kind);
+            allocator.free(e.abi);
+        }
+        allocator.free(manifest.exports);
+        for (manifest.roots) |r| {
+            allocator.free(r.role);
+        }
+        allocator.free(manifest.roots);
+    }
+
+    var export_hash: ?Hash = null;
+    for (manifest.exports) |e| {
+        if (std.mem.eql(u8, e.name, export_name)) {
+            export_hash = e.root;
+            break;
+        }
+    }
+    const root_hash = export_hash orelse return error.ExportNotFound;
+
+    var np = Parser.init(nodes_bytes);
+    var payloads = try parseNodeSection(&np, allocator);
+    defer payloads.deinit();
+
+    var cache = std.AutoHashMap(Hash, u32).init(allocator);
+    defer cache.deinit();
+
+    return try loadNode(arena, payloads, &cache, root_hash);
+}
+
+/// Parse an Arboricx bundle and load the default (first) root into the arena.
+pub fn loadBundleDefaultRoot(
+    arena: *Arena,
+    bundle_bytes: []const u8,
+) Error!u32 {
+    var p = Parser.init(bundle_bytes);
+
+    const header = try parseHeader(&p);
+
+    p.pos = @intCast(header.dir_offset);
+    const allocator = arena.allocator;
+    const entries = try parseSectionEntries(&p, header.section_count, allocator);
+    defer allocator.free(entries);
+
+    var manifest_entry: ?SectionEntry = null;
+    var nodes_entry: ?SectionEntry = null;
+    for (entries) |entry| {
+        if (entry.section_type == 1) manifest_entry = entry;
+        if (entry.section_type == 2) nodes_entry = entry;
+    }
+    const manifest_section = manifest_entry orelse return error.InvalidManifest;
+    const nodes_section = nodes_entry orelse return error.InvalidNodePayload;
+
+    const manifest_bytes = bundle_bytes[@intCast(manifest_section.offset)..@intCast(manifest_section.offset + manifest_section.length)];
+    if (!std.mem.eql(u8, &sha256Digest(manifest_bytes), &manifest_section.digest)) return error.DigestMismatch;
+
+    const nodes_bytes = bundle_bytes[@intCast(nodes_section.offset)..@intCast(nodes_section.offset + nodes_section.length)];
+    if (!std.mem.eql(u8, &sha256Digest(nodes_bytes), &nodes_section.digest)) return error.DigestMismatch;
+
+    var mp = Parser.init(manifest_bytes);
+    const manifest = try parseManifest(&mp, allocator);
+    defer {
+        for (manifest.exports) |e| {
+            allocator.free(e.name);
+            allocator.free(e.kind);
+            allocator.free(e.abi);
+        }
+        allocator.free(manifest.exports);
+        for (manifest.roots) |r| {
+            allocator.free(r.role);
+        }
+        allocator.free(manifest.roots);
+    }
+
+    if (manifest.roots.len == 0) return error.ExportNotFound;
+    const root_hash = manifest.roots[0].hash;
+
+    var np = Parser.init(nodes_bytes);
+    var payloads = try parseNodeSection(&np, allocator);
+    defer payloads.deinit();
+
+    var cache = std.AutoHashMap(Hash, u32).init(allocator);
+    defer cache.deinit();
+
+    return try loadNode(arena, payloads, &cache, root_hash);
+}

ext/zig/src/c_abi.zig

@@ -0,0 +1,183 @@
+const std = @import("std");
+const tree = @import("tree.zig");
+const Arena = @import("arena.zig").Arena;
+const reduce = @import("reduce.zig");
+const codecs = @import("codecs.zig");
+const kernel = @import("kernel.zig");
+const bundle = @import("bundle.zig");
+
+/// Opaque handle for the C API.  Layout is not exposed to C.
+/// Holds a persistent arena for user-built terms and the kernel.
+pub const ArbCtx = struct {
+    gpa: std.mem.Allocator,
+    arena: Arena,
+    kernel_root: u32,
+};
+
+// ---------------------------------------------------------------------------
+// Context lifecycle
+// ---------------------------------------------------------------------------
+
+export fn arboricx_init() ?*ArbCtx {
+    const ptr = std.heap.smp_allocator.create(ArbCtx) catch return null;
+    ptr.gpa = std.heap.smp_allocator;
+    ptr.arena = Arena.init(std.heap.smp_allocator);
+    ptr.kernel_root = kernel.loadKernel(&ptr.arena) catch {
+        ptr.arena.deinit();
+        std.heap.smp_allocator.destroy(ptr);
+        return null;
+    };
+    return ptr;
+}
+
+export fn arboricx_free(ctx: *ArbCtx) void {
+    ctx.arena.deinit();
+    ctx.gpa.destroy(ctx);
+}
+
+export fn arboricx_free_buf(_: *ArbCtx, ptr: [*]u8, len: usize) void {
+    std.heap.smp_allocator.free(ptr[0..len]);
+}
+
+// ---------------------------------------------------------------------------
+// Tree construction  (all write into the persistent arena)
+// ---------------------------------------------------------------------------
+
+export fn arb_leaf(ctx: *ArbCtx) u32 {
+    return ctx.arena.alloc(.leaf) catch 0;
+}
+
+export fn arb_stem(ctx: *ArbCtx, child: u32) u32 {
+    return ctx.arena.alloc(.{ .stem = .{ .child = child } }) catch 0;
+}
+
+export fn arb_fork(ctx: *ArbCtx, left: u32, right: u32) u32 {
+    return ctx.arena.alloc(.{ .fork = .{ .left = left, .right = right } }) catch 0;
+}
+
+export fn arb_app(ctx: *ArbCtx, func: u32, arg: u32) u32 {
+    return ctx.arena.alloc(.{ .app = .{ .func = func, .arg = arg } }) catch 0;
+}
+
+// ---------------------------------------------------------------------------
+// Reduction
+// ---------------------------------------------------------------------------
+/// Reduces `root` in a *fresh* scratch arena so that garbage from previous
+/// reductions never accumulates.  The kernel and term are deep-copied into
+/// the scratch arena, reduced there, and the result is copied back into the
+/// persistent arena.
+// ---------------------------------------------------------------------------
+
+export fn arb_reduce(ctx: *ArbCtx, root: u32, fuel: u64) u32 {
+    // 1. Fresh scratch arena
+    var scratch = Arena.init(ctx.gpa);
+    defer scratch.deinit();
+
+    // 2. Deep-copy the term (which may reference kernel nodes) into scratch
+    const scratch_root = tree.copyTree(ctx.arena.nodes.items, &scratch, root) catch return 0;
+
+    // 3. Reduce in scratch
+    const scratch_result = reduce.reduce(scratch_root, &scratch, fuel) catch return 0;
+
+    // 4. Copy the result back to the persistent arena
+    return tree.copyTree(scratch.nodes.items, &ctx.arena, scratch_result) catch 0;
+}
+
+// ---------------------------------------------------------------------------
+// Codec constructors
+// ---------------------------------------------------------------------------
+
+export fn arb_of_number(ctx: *ArbCtx, n: u64) u32 {
+    return codecs.ofNumber(&ctx.arena, n) catch 0;
+}
+
+export fn arb_of_string(ctx: *ArbCtx, s: [*:0]const u8) u32 {
+    const slice = std.mem.sliceTo(s, 0);
+    return codecs.ofString(&ctx.arena, slice) catch 0;
+}
+
+export fn arb_of_bytes(ctx: *ArbCtx, bytes: [*]const u8, len: usize) u32 {
+    return codecs.ofBytes(&ctx.arena, bytes[0..len]) catch 0;
+}
+
+export fn arb_of_list(ctx: *ArbCtx, items: [*]const u32, len: usize) u32 {
+    return codecs.ofList(&ctx.arena, items[0..len]) catch 0;
+}
+
+// ---------------------------------------------------------------------------
+// Codec destructors
+// Return 1 on success, 0 on failure.
+// ---------------------------------------------------------------------------
+
+export fn arb_to_number(ctx: *ArbCtx, root: u32, out: *u64) c_int {
+    const n = codecs.toNumber(&ctx.arena, root) catch return 0;
+    if (n == null) return 0;
+    out.* = n.?;
+    return 1;
+}
+
+export fn arb_to_string(ctx: *ArbCtx, root: u32, out_ptr: **u8, out_len: *usize) c_int {
+    const s = codecs.toString(&ctx.arena, root) catch return 0;
+    if (s == null) return 0;
+    out_ptr.* = @ptrCast(s.?.ptr);
+    out_len.* = s.?.len;
+    return 1;
+}
+
+export fn arb_to_bytes(ctx: *ArbCtx, root: u32, out_ptr: **u8, out_len: *usize) c_int {
+    return arb_to_string(ctx, root, out_ptr, out_len);
+}
+
+export fn arb_to_bool(ctx: *ArbCtx, root: u32, out: *c_int) c_int {
+    const b = codecs.toBool(&ctx.arena, root) catch return 0;
+    if (b == null) return 0;
+    out.* = if (b.?) 1 else 0;
+    return 1;
+}
+
+// ---------------------------------------------------------------------------
+// Result unwrapping
+// Return 1 on success, 0 on failure.
+// ---------------------------------------------------------------------------
+
+export fn arb_unwrap_result(ctx: *ArbCtx, root: u32, out_ok: *c_int, out_value: *u32, out_rest: *u32) c_int {
+    const r = codecs.unwrapResult(&ctx.arena, root) catch return 0;
+    if (r == null) return 0;
+    out_ok.* = if (r.?.ok) 1 else 0;
+    out_value.* = r.?.value;
+    out_rest.* = r.?.rest;
+    return 1;
+}
+
+export fn arb_unwrap_host_value(ctx: *ArbCtx, root: u32, out_tag: *u64, out_payload: *u32) c_int {
+    const hv = codecs.unwrapHostValue(&ctx.arena, root) catch return 0;
+    if (hv == null) return 0;
+    out_tag.* = hv.?.tag;
+    out_payload.* = hv.?.payload;
+    return 1;
+}
+
+// ---------------------------------------------------------------------------
+// Kernel entrypoints
+// ---------------------------------------------------------------------------
+
+export fn arb_kernel_root(ctx: *ArbCtx) u32 {
+    return ctx.kernel_root;
+}
+
+// ---------------------------------------------------------------------------
+// Native bundle loading (fast path — bypasses the Tricu kernel)
+// ---------------------------------------------------------------------------
+
+/// Load a named export from an Arboricx bundle directly into the arena.
+/// Returns the arena index of the exported term, or 0 on error.
+export fn arb_load_bundle(ctx: *ArbCtx, bytes: [*]const u8, len: usize, name: [*:0]const u8) u32 {
+    const name_slice = std.mem.sliceTo(name, 0);
+    return bundle.loadBundleExport(&ctx.arena, bytes[0..len], name_slice) catch 0;
+}
+
+/// Load the default root from an Arboricx bundle directly into the arena.
+/// Returns the arena index of the root term, or 0 on error.
+export fn arb_load_bundle_default(ctx: *ArbCtx, bytes: [*]const u8, len: usize) u32 {
+    return bundle.loadBundleDefaultRoot(&ctx.arena, bytes[0..len]) catch 0;
+}

ext/zig/src/codecs.zig

@@ -0,0 +1,205 @@
+const std = @import("std");
+const tree = @import("tree.zig");
+const Arena = @import("arena.zig").Arena;
+const reduce = @import("reduce.zig");
+
+// ---------------------------------------------------------------------------
+// Number encoding/decoding
+// ---------------------------------------------------------------------------
+
+pub fn ofNumber(arena: *Arena, n: u64) !u32 {
+    if (n == 0) {
+        return try arena.alloc(.leaf);
+    }
+    const bit = if (n % 2 == 1) try arena.alloc(.{ .stem = .{ .child = try arena.alloc(.leaf) } }) else try arena.alloc(.leaf);
+    const rest = try ofNumber(arena, n / 2);
+    return try arena.alloc(.{ .fork = .{ .left = bit, .right = rest } });
+}
+
+pub fn toNumber(arena: *Arena, idx: u32) !?u64 {
+    const node = try reduce.reduce(idx, arena, 10_000);
+    const n = arena.get(node);
+    return switch (n.*) {
+        .leaf => 0,
+        .stem => return null,
+        .fork => |f| blk: {
+            const bit_node = try reduce.reduce(f.left, arena, 10_000);
+            const bit = arena.get(bit_node);
+            const bit_val: u64 = switch (bit.*) {
+                .leaf => 0,
+                .stem => |s| if (arena.get(s.child).* == .leaf) 1 else return null,
+                else => return null,
+            };
+            const rest = try toNumber(arena, f.right) orelse return null;
+            break :blk bit_val + 2 * rest;
+        },
+        .app => return null,
+    };
+}
+
+// ---------------------------------------------------------------------------
+// List encoding/decoding
+// ---------------------------------------------------------------------------
+
+pub fn ofList(arena: *Arena, items: []const u32) !u32 {
+    var result = try arena.alloc(.leaf);
+    var i: usize = items.len;
+    while (i > 0) {
+        i -= 1;
+        result = try arena.alloc(.{ .fork = .{ .left = items[i], .right = result } });
+    }
+    return result;
+}
+
+pub fn toList(arena: *Arena, idx: u32) !?std.ArrayList(u32) {
+    var result = std.ArrayList(u32).empty;
+    errdefer result.deinit(arena.allocator);
+
+    var current = idx;
+    while (true) {
+        const node = try reduce.reduce(current, arena, 10_000);
+        const n = arena.get(node);
+        switch (n.*) {
+            .leaf => return result,
+            .stem => return null,
+            .fork => |f| {
+                try result.append(arena.allocator, f.left);
+                current = f.right;
+            },
+            .app => return null,
+        }
+    }
+}
+
+// ---------------------------------------------------------------------------
+// String / Bytes encoding/decoding
+// Strings are lists of byte values (each character encoded as a number tree).
+// ---------------------------------------------------------------------------
+
+pub fn ofString(arena: *Arena, s: []const u8) !u32 {
+    var bytes = try arena.allocator.alloc(u32, s.len);
+    defer arena.allocator.free(bytes);
+    for (s, 0..) |c, i| {
+        bytes[i] = try ofNumber(arena, c);
+    }
+    return try ofList(arena, bytes);
+}
+
+pub fn toString(arena: *Arena, idx: u32) !?[]u8 {
+    var list = try toList(arena, idx) orelse return null;
+    defer list.deinit(arena.allocator);
+    var result = try arena.allocator.alloc(u8, list.items.len);
+    errdefer arena.allocator.free(result);
+    for (list.items, 0..) |elem_idx, i| {
+        const num = try toNumber(arena, elem_idx) orelse {
+            arena.allocator.free(result);
+            return null;
+        };
+        if (num > 255) {
+            arena.allocator.free(result);
+            return null;
+        }
+        result[i] = @intCast(num);
+    }
+    return result;
+}
+
+pub fn ofBytes(arena: *Arena, bytes: []const u8) !u32 {
+    return try ofString(arena, bytes);
+}
+
+pub fn toBytes(arena: *Arena, idx: u32) !?[]u8 {
+    return try toString(arena, idx);
+}
+
+// ---------------------------------------------------------------------------
+// Result unwrapping (ok/err protocol)
+// ok value rest = pair true (pair value rest)
+// err code rest = pair false (pair code rest)
+// ---------------------------------------------------------------------------
+
+pub const UnwrapResult = struct {
+    ok: bool,
+    value: u32,
+    rest: u32,
+};
+
+pub fn unwrapResult(arena: *Arena, idx: u32) !?UnwrapResult {
+    const node = try reduce.reduce(idx, arena, 10_000);
+    const n = arena.get(node);
+    switch (n.*) {
+        .fork => |f| {
+            const tag = try reduce.reduce(f.left, arena, 10_000);
+            const rest_pair = try reduce.reduce(f.right, arena, 10_000);
+            const rp = arena.get(rest_pair);
+            switch (rp.*) {
+                .fork => |rf| {
+                    const is_ok = tree.sameTree(arena, tag, try arena.alloc(.{ .stem = .{ .child = try arena.alloc(.leaf) } }));
+                    return UnwrapResult{
+                        .ok = is_ok,
+                        .value = rf.left,
+                        .rest = rf.right,
+                    };
+                },
+                else => return null,
+            }
+        },
+        else => return null,
+    }
+}
+
+// ---------------------------------------------------------------------------
+// Host ABI value unwrapping
+// A host ABI value is: pair tag payload
+// ---------------------------------------------------------------------------
+
+pub const HostValue = struct {
+    tag: u64,
+    payload: u32,
+};
+
+pub fn unwrapHostValue(arena: *Arena, idx: u32) !?HostValue {
+    const node = try reduce.reduce(idx, arena, 10_000);
+    const n = arena.get(node);
+    switch (n.*) {
+        .fork => |f| {
+            const tag_num = try toNumber(arena, f.left) orelse return null;
+            return HostValue{ .tag = tag_num, .payload = f.right };
+        },
+        else => return null,
+    }
+}
+
+/// Returns true if the tree is a valid boolean (Leaf=false, Stem Leaf=true).
+pub fn isBool(arena: *Arena, idx: u32) !bool {
+    const node = try reduce.reduce(idx, arena, 10_000);
+    const n = arena.get(node);
+    return switch (n.*) {
+        .leaf => true,
+        .stem => |s| arena.get(s.child).* == .leaf,
+        else => false,
+    };
+}
+
+/// Extract the boolean value: false for Leaf, true for Stem Leaf.
+/// Returns null if the tree is not a valid boolean.
+pub fn toBool(arena: *Arena, idx: u32) !?bool {
+    const node = try reduce.reduce(idx, arena, 10_000);
+    const n = arena.get(node);
+    return switch (n.*) {
+        .leaf => false,
+        .stem => |s| if (arena.get(s.child).* == .leaf) true else null,
+        else => null,
+    };
+}
+
+// ---------------------------------------------------------------------------
+// Host ABI tag constants
+// ---------------------------------------------------------------------------
+
+pub const HOST_TREE_TAG: u64 = 0;
+pub const HOST_STRING_TAG: u64 = 1;
+pub const HOST_NUMBER_TAG: u64 = 2;
+pub const HOST_BOOL_TAG: u64 = 3;
+pub const HOST_LIST_TAG: u64 = 4;
+pub const HOST_BYTES_TAG: u64 = 5;

ext/zig/src/kernel.zig

@@ -0,0 +1,22 @@
+const std = @import("std");
+const tree = @import("tree.zig");
+const Arena = @import("arena.zig").Arena;
+const embed = @import("kernel_embed");
+
+/// Copy the embedded kernel into an arena, returning the new root index.
+/// This allows the kernel to be used in App nodes alongside application terms.
+pub fn loadKernel(arena: *Arena) !u32 {
+    var mapping = try arena.allocator.alloc(u32, embed.kernel_nodes.len);
+    defer arena.allocator.free(mapping);
+
+    for (embed.kernel_nodes, 0..) |node, i| {
+        const idx: u32 = @intCast(i);
+        mapping[idx] = switch (node) {
+            .leaf => try arena.alloc(.leaf),
+            .stem => |s| try arena.alloc(.{ .stem = .{ .child = mapping[s.child] } }),
+            .fork => |f| try arena.alloc(.{ .fork = .{ .left = mapping[f.left], .right = mapping[f.right] } }),
+        };
+    }
+
+    return mapping[embed.kernel_root];
+}

ext/zig/src/main.zig

@@ -0,0 +1,235 @@
+const std = @import("std");
+const tree = @import("tree.zig");
+const Arena = @import("arena.zig").Arena;
+const reduce = @import("reduce.zig");
+const codecs = @import("codecs.zig");
+const kernel = @import("kernel.zig");
+const bundle = @import("bundle.zig");
+
+fn runNative(arena: *Arena, tag: u64, bundle_bytes: []const u8, args_raw: []const []const u8, io: std.Io) !void {
+    const term = try bundle.loadBundleDefaultRoot(arena, bundle_bytes);
+
+    var current = term;
+    for (args_raw) |arg| {
+        const arg_tree = try parseArg(arena, arg);
+        current = try arena.alloc(.{ .app = .{ .func = current, .arg = arg_tree } });
+    }
+
+    const result = try reduce.reduce(current, arena, 1_000_000_000);
+
+    var stdout_buf: [4096]u8 = undefined;
+    var stdout = std.Io.File.stdout().writer(io, &stdout_buf);
+
+    switch (tag) {
+        codecs.HOST_STRING_TAG => {
+            const s = try codecs.toString(arena, result) orelse {
+                try stdout.interface.writeAll("Error: failed to decode string result\n");
+                try stdout.flush();
+                return error.DecodeFailed;
+            };
+            defer arena.allocator.free(s);
+            try stdout.interface.writeAll(s);
+            try stdout.interface.writeAll("\n");
+        },
+        codecs.HOST_NUMBER_TAG => {
+            const n = try codecs.toNumber(arena, result) orelse 0;
+            try stdout.interface.print("{d}\n", .{n});
+        },
+        codecs.HOST_BOOL_TAG => {
+            const b = try codecs.toBool(arena, result) orelse {
+                try stdout.interface.writeAll("Error: failed to decode bool result\n");
+                try stdout.flush();
+                return error.DecodeFailed;
+            };
+            try stdout.interface.writeAll(if (b) "true\n" else "false\n");
+        },
+        codecs.HOST_TREE_TAG => {
+            try tree.formatTree(&stdout.interface, arena, result, 0);
+            try stdout.interface.writeAll("\n");
+        },
+        else => {
+            try stdout.interface.print("(tag={d}, payload=", .{tag});
+            try tree.formatTree(&stdout.interface, arena, result, 0);
+            try stdout.interface.writeAll(")\n");
+        },
+    }
+    try stdout.flush();
+}
+
+fn runBundle(arena: *Arena, tag: u64, bundle_bytes: []const u8, args_raw: []const []const u8, io: std.Io) !void {
+    const kernel_root = try kernel.loadKernel(arena);
+
+    const tag_tree = try codecs.ofNumber(arena, tag);
+    const bundle_tree = try codecs.ofBytes(arena, bundle_bytes);
+
+    var arg_items = try arena.allocator.alloc(u32, args_raw.len);
+    defer arena.allocator.free(arg_items);
+    for (args_raw, 0..) |arg, i| {
+        arg_items[i] = try parseArg(arena, arg);
+    }
+    const args_tree = try codecs.ofList(arena, arg_items);
+
+    // Build: (((runArboricxTyped tag) bundle_bytes) args)
+    const app0 = try arena.alloc(.{ .app = .{ .func = kernel_root, .arg = tag_tree } });
+    const app1 = try arena.alloc(.{ .app = .{ .func = app0, .arg = bundle_tree } });
+    const app2 = try arena.alloc(.{ .app = .{ .func = app1, .arg = args_tree } });
+
+    const result = try reduce.reduce(app2, arena, 1_000_000_000);
+
+    const unwrapped = try codecs.unwrapResult(arena, result) orelse {
+        var stderr = std.Io.File.stderr().writer(io, &[_]u8{});
+        try stderr.interface.writeAll("Error: result is not a valid ok/err pair\n");
+        try stderr.flush();
+        return error.InvalidResult;
+    };
+
+    if (!unwrapped.ok) {
+        var stderr = std.Io.File.stderr().writer(io, &[_]u8{});
+        const code = try codecs.toNumber(arena, unwrapped.value) orelse 0;
+        try stderr.interface.print("Error: kernel returned err, code={d}\n", .{code});
+        try stderr.flush();
+        return error.KernelError;
+    }
+
+    const hv = try codecs.unwrapHostValue(arena, unwrapped.value) orelse {
+        var stderr = std.Io.File.stderr().writer(io, &[_]u8{});
+        try stderr.interface.writeAll("Error: result is not a valid host ABI value\n");
+        try stderr.flush();
+        return error.InvalidHostValue;
+    };
+
+    var stdout_buf: [4096]u8 = undefined;
+    var stdout = std.Io.File.stdout().writer(io, &stdout_buf);
+
+    switch (hv.tag) {
+        codecs.HOST_STRING_TAG => {
+            const s = try codecs.toString(arena, hv.payload) orelse {
+                try stdout.interface.writeAll("Error: failed to decode string payload\n");
+                try stdout.flush();
+                return error.DecodeFailed;
+            };
+            defer arena.allocator.free(s);
+            try stdout.interface.writeAll(s);
+            try stdout.interface.writeAll("\n");
+        },
+        codecs.HOST_NUMBER_TAG => {
+            const n = try codecs.toNumber(arena, hv.payload) orelse 0;
+            try stdout.interface.print("{d}\n", .{n});
+        },
+        codecs.HOST_BOOL_TAG => {
+            const b = try codecs.toBool(arena, hv.payload) orelse {
+                try stdout.interface.writeAll("Error: failed to decode bool payload\n");
+                try stdout.flush();
+                return error.DecodeFailed;
+            };
+            try stdout.interface.writeAll(if (b) "true\n" else "false\n");
+        },
+        codecs.HOST_TREE_TAG => {
+            try tree.formatTree(&stdout.interface, arena, hv.payload, 0);
+            try stdout.interface.writeAll("\n");
+        },
+        else => {
+            try stdout.interface.print("(tag={d}, payload=", .{hv.tag});
+            try tree.formatTree(&stdout.interface, arena, hv.payload, 0);
+            try stdout.interface.writeAll(")\n");
+        },
+    }
+    try stdout.flush();
+}
+
+fn parseArg(arena: *Arena, s: []const u8) !u32 {
+    if (std.fmt.parseInt(u64, s, 10)) |n| {
+        return try codecs.ofNumber(arena, n);
+    } else |_| {}
+
+    if (s.len >= 2 and s[0] == '"' and s[s.len - 1] == '"') {
+        return try codecs.ofString(arena, s[1 .. s.len - 1]);
+    }
+
+    return try codecs.ofString(arena, s);
+}
+
+pub fn main(init: std.process.Init) !void {
+    const gpa = init.gpa;
+    const io = init.io;
+
+    const args = try init.minimal.args.toSlice(init.arena.allocator());
+    if (args.len < 2) {
+        var stderr = std.Io.File.stderr().writer(io, &[_]u8{});
+        try stderr.interface.writeAll("Usage: tricu-zig [--type TYPE] [--kernel] <bundle.arboricx> [arg1 arg2 ...]\n");
+        try stderr.flush();
+        std.process.exit(1);
+    }
+
+    // Parse options before bundle path
+    var tag = codecs.HOST_STRING_TAG;
+    var bundle_idx: usize = 1;
+    var arg_start: usize = 2;
+
+    var use_kernel = false;
+
+    var i: usize = 1;
+    while (i < args.len) : (i += 1) {
+        if (std.mem.eql(u8, args[i], "--type")) {
+            if (i + 1 >= args.len) {
+                var stderr = std.Io.File.stderr().writer(io, &[_]u8{});
+                try stderr.interface.writeAll("Usage: tricu-zig --type <tree|number|bool|string|list|bytes> <bundle> [args...]\n");
+                try stderr.flush();
+                std.process.exit(1);
+            }
+            const type_str = args[i + 1];
+            tag = if (std.mem.eql(u8, type_str, "tree")) codecs.HOST_TREE_TAG
+                else if (std.mem.eql(u8, type_str, "number")) codecs.HOST_NUMBER_TAG
+                else if (std.mem.eql(u8, type_str, "bool")) codecs.HOST_BOOL_TAG
+                else if (std.mem.eql(u8, type_str, "string")) codecs.HOST_STRING_TAG
+                else if (std.mem.eql(u8, type_str, "list")) codecs.HOST_LIST_TAG
+                else if (std.mem.eql(u8, type_str, "bytes")) codecs.HOST_BYTES_TAG
+                else blk: {
+                    var stderr = std.Io.File.stderr().writer(io, &[_]u8{});
+                    try stderr.interface.print("Unknown type: {s}\n", .{type_str});
+                    try stderr.flush();
+                    std.process.exit(1);
+                    break :blk codecs.HOST_STRING_TAG;
+                };
+            i += 1;
+        } else if (std.mem.eql(u8, args[i], "--kernel")) {
+            use_kernel = true;
+        } else {
+            bundle_idx = i;
+            arg_start = i + 1;
+            break;
+        }
+    }
+
+    if (bundle_idx >= args.len) {
+        var stderr = std.Io.File.stderr().writer(io, &[_]u8{});
+        try stderr.interface.writeAll("Usage: tricu-zig [--type TYPE] [--kernel] <bundle.arboricx> [arg1 arg2 ...]\n");
+        try stderr.flush();
+        std.process.exit(1);
+    }
+
+    const bundle_path = args[bundle_idx];
+    const bundle_bytes = try std.Io.Dir.cwd().readFileAlloc(io, bundle_path, gpa, .limited(10 * 1024 * 1024));
+    defer gpa.free(bundle_bytes);
+
+    var arena = Arena.init(gpa);
+    defer arena.deinit();
+
+    const call_args = if (arg_start < args.len) args[arg_start..] else &[_][]const u8{};
+
+    if (use_kernel) {
+        runBundle(&arena, tag, bundle_bytes, call_args, io) catch |err| {
+            var stderr = std.Io.File.stderr().writer(io, &[_]u8{});
+            try stderr.interface.print("Execution failed: {s}\n", .{@errorName(err)});
+            try stderr.flush();
+            std.process.exit(1);
+        };
+    } else {
+        runNative(&arena, tag, bundle_bytes, call_args, io) catch |err| {
+            var stderr = std.Io.File.stderr().writer(io, &[_]u8{});
+            try stderr.interface.print("Execution failed: {s}\n", .{@errorName(err)});
+            try stderr.flush();
+            std.process.exit(1);
+        };
+    }
+}

ext/zig/src/reduce.zig

@@ -0,0 +1,128 @@
+const std = @import("std");
+const tree = @import("tree.zig");
+const Arena = @import("arena.zig").Arena;
+
+pub const ReduceError = error{
+    FuelExhausted,
+    InvalidApply,
+    OutOfMemory,
+};
+
+/// Reduce a term to weak head normal form.
+pub fn reduce(root: u32, arena: *Arena, fuel: u64) ReduceError!u32 {
+    var remaining = fuel;
+    return try whnf(root, arena, &remaining);
+}
+
+fn whnf(term: u32, arena: *Arena, fuel: *u64) ReduceError!u32 {
+    if (fuel.* == 0) return error.FuelExhausted;
+    var current = term;
+
+    while (true) {
+        switch (arena.get(current).*) {
+            .leaf, .stem, .fork => return current,
+            .app => |app| {
+                const orig = current;
+                const func_idx = app.func;
+                const arg_idx = app.arg;
+
+                // Reduce function to WHNF
+                const f = try whnf(func_idx, arena, fuel);
+                if (fuel.* == 0) return error.FuelExhausted;
+                fuel.* -= 1;
+
+                switch (arena.get(f).*) {
+                    // apply Leaf b = Stem b
+                    .leaf => {
+                        arena.get(orig).* = .{ .stem = .{ .child = arg_idx } };
+                        return orig;
+                    },
+                    // apply (Stem a) b = Fork a b
+                    .stem => |s| {
+                        const a = s.child;
+                        arena.get(orig).* = .{ .fork = .{ .left = a, .right = arg_idx } };
+                        return orig;
+                    },
+                    .fork => |fork_f| {
+                        const left_idx = fork_f.left;
+                        const right_idx = fork_f.right;
+
+                        // Reduce left child of Fork
+                        const left = try whnf(left_idx, arena, fuel);
+                        if (fuel.* == 0) return error.FuelExhausted;
+                        fuel.* -= 1;
+
+                        switch (arena.get(left).*) {
+                            // apply (Fork Leaf a) _ = a
+                            .leaf => {
+                                const result = try whnf(right_idx, arena, fuel);
+                                if (fuel.* == 0) return error.FuelExhausted;
+                                fuel.* -= 1;
+                                if (orig != result) {
+                                    arena.get(orig).* = arena.get(result).*;
+                                }
+                                return orig;
+                            },
+                            // apply (Fork (Stem a) b) c = (a c) (b c)
+                            .stem => |s| {
+                                const a = s.child;
+                                const inner1 = try arena.alloc(.{ .app = .{ .func = a, .arg = arg_idx } });
+                                const inner2 = try arena.alloc(.{ .app = .{ .func = right_idx, .arg = arg_idx } });
+                                arena.get(orig).* = .{ .app = .{ .func = inner1, .arg = inner2 } };
+                                current = orig;
+                                if (fuel.* == 0) return error.FuelExhausted;
+                                fuel.* -= 1;
+                                continue;
+                            },
+                            .fork => {
+                                // Reduce argument
+                                const arg = try whnf(arg_idx, arena, fuel);
+                                if (fuel.* == 0) return error.FuelExhausted;
+                                fuel.* -= 1;
+
+                                switch (arena.get(arg).*) {
+                                    // apply (Fork (Fork a b) c) Leaf = a
+                                    .leaf => {
+                                        const a_idx = arena.get(left).fork.left;
+                                        const result = try whnf(a_idx, arena, fuel);
+                                        if (fuel.* == 0) return error.FuelExhausted;
+                                        fuel.* -= 1;
+                                        if (orig != result) {
+                                            arena.get(orig).* = arena.get(result).*;
+                                        }
+                                        return orig;
+                                    },
+                                    // apply (Fork (Fork a b) c) (Stem u) = b u
+                                    .stem => |s| {
+                                        const b_idx = arena.get(left).fork.right;
+                                        const u = s.child;
+                                        arena.get(orig).* = .{ .app = .{ .func = b_idx, .arg = u } };
+                                        current = orig;
+                                        if (fuel.* == 0) return error.FuelExhausted;
+                                        fuel.* -= 1;
+                                        continue;
+                                    },
+                                    // apply (Fork (Fork a b) c) (Fork u v) = (c u) v
+                                    .fork => |arg_fork| {
+                                        const c_idx = right_idx;
+                                        const u = arg_fork.left;
+                                        const v = arg_fork.right;
+                                        const inner = try arena.alloc(.{ .app = .{ .func = c_idx, .arg = u } });
+                                        arena.get(orig).* = .{ .app = .{ .func = inner, .arg = v } };
+                                        current = orig;
+                                        if (fuel.* == 0) return error.FuelExhausted;
+                                        fuel.* -= 1;
+                                        continue;
+                                    },
+                                    .app => return error.InvalidApply,
+                                }
+                            },
+                            .app => return error.InvalidApply,
+                        }
+                    },
+                    .app => return error.InvalidApply,
+                }
+            },
+        }
+    }
+}

ext/zig/src/ternary.zig

@@ -0,0 +1,27 @@
+const std = @import("std");
+const tree = @import("tree.zig");
+const Arena = @import("arena.zig").Arena;
+
+pub fn parseTernary(source: []const u8, arena: *Arena) !u32 {
+    var pos: usize = 0;
+    return try parseTernaryRec(source, &pos, arena);
+}
+
+fn parseTernaryRec(source: []const u8, pos: *usize, arena: *Arena) !u32 {
+    if (pos.* >= source.len) return error.UnexpectedEnd;
+    const ch = source[pos.*];
+    pos.* += 1;
+    return switch (ch) {
+        '0' => try arena.alloc(.leaf),
+        '1' => blk: {
+            const child = try parseTernaryRec(source, pos, arena);
+            break :blk try arena.alloc(.{ .stem = .{ .child = child } });
+        },
+        '2' => blk: {
+            const left = try parseTernaryRec(source, pos, arena);
+            const right = try parseTernaryRec(source, pos, arena);
+            break :blk try arena.alloc(.{ .fork = .{ .left = left, .right = right } });
+        },
+        else => error.InvalidChar,
+    };
+}

ext/zig/src/tree.zig

@@ -0,0 +1,191 @@
+const std = @import("std");
+
+pub const NodeTag = enum(u8) {
+    leaf = 0,
+    stem = 1,
+    fork = 2,
+    app = 3,
+};
+
+pub const Node = union(NodeTag) {
+    leaf,
+    stem: struct { child: u32 },
+    fork: struct { left: u32, right: u32 },
+    app: struct { func: u32, arg: u32 },
+
+    pub fn leafNode() Node {
+        return .leaf;
+    }
+
+    pub fn stemNode(child: u32) Node {
+        return .{ .stem = .{ .child = child } };
+    }
+
+    pub fn forkNode(left: u32, right: u32) Node {
+        return .{ .fork = .{ .left = left, .right = right } };
+    }
+
+    pub fn appNode(func: u32, arg: u32) Node {
+        return .{ .app = .{ .func = func, .arg = arg } };
+    }
+};
+
+pub const NodePool = struct {
+    allocator: std.mem.Allocator,
+    nodes: std.ArrayList(Node),
+
+    pub fn init(allocator: std.mem.Allocator) NodePool {
+        return .{
+            .allocator = allocator,
+            .nodes = .empty,
+        };
+    }
+
+    pub fn deinit(self: *NodePool) void {
+        self.nodes.deinit(self.allocator);
+    }
+
+    pub fn push(self: *NodePool, node: Node) !u32 {
+        const idx: u32 = @intCast(self.nodes.items.len);
+        try self.nodes.append(self.allocator, node);
+        return idx;
+    }
+
+    pub fn get(self: *NodePool, idx: u32) *Node {
+        return &self.nodes.items[idx];
+    }
+
+    pub fn len(self: *const NodePool) u32 {
+        return @intCast(self.nodes.items.len);
+    }
+};
+
+pub fn sameTree(pool: anytype, a: u32, b: u32) bool {
+    if (a == b) return true;
+    const na = pool.nodes.items[a];
+    const nb = pool.nodes.items[b];
+    if (@intFromEnum(na) != @intFromEnum(nb)) return false;
+    return switch (na) {
+        .leaf => true,
+        .stem => |sa| sameTree(pool, sa.child, nb.stem.child),
+        .fork => |fa| sameTree(pool, fa.left, nb.fork.left) and sameTree(pool, fa.right, nb.fork.right),
+        .app => |aa| sameTree(pool, aa.func, nb.app.func) and sameTree(pool, aa.arg, nb.app.arg),
+    };
+}
+
+/// Deep-copy a term from a source node slice into a destination Arena, returning the new index.
+/// Uses recursion; assumes the tree is finite and well-formed.
+const DstArena = @import("arena.zig").Arena;
+
+/// Iterative deep-copy of a DAG from `src` into `dst`.  Uses an explicit
+/// heap-allocated stack so that very deep (e.g. long list) trees do not
+/// blow the native C stack.  Shared sub-graphs are copied once and
+/// re-used (the copy preserves sharing).
+pub fn copyTree(src: []const Node, dst: *DstArena, root: u32) !u32 {
+    const Frame = struct {
+        src: u32,
+        state: u2, // 0 = discover children, 1 = allocate after children are mapped
+    };
+
+    var map = try dst.allocator.alloc(u32, src.len);
+    defer dst.allocator.free(map);
+    @memset(std.mem.sliceAsBytes(map), 0xFF);
+
+    var stack = try dst.allocator.alloc(Frame, src.len);
+    defer dst.allocator.free(stack);
+    var sp: usize = 0;
+
+    stack[sp] = .{ .src = root, .state = 0 };
+    sp += 1;
+
+    while (sp > 0) {
+        const frame = &stack[sp - 1];
+        const src_idx = frame.src;
+
+        if (map[src_idx] != 0xFFFFFFFF) {
+            sp -= 1;
+            continue;
+        }
+
+        if (frame.state == 0) {
+            frame.state = 1;
+            const node = src[src_idx];
+            switch (node) {
+                .leaf => {}, // no children, fall through to allocation next iteration
+                .stem => |s| {
+                    if (map[s.child] == 0xFFFFFFFF) {
+                        stack[sp] = .{ .src = s.child, .state = 0 };
+                        sp += 1;
+                    }
+                },
+                .fork => |f| {
+                    const need_left = map[f.left] == 0xFFFFFFFF;
+                    const need_right = map[f.right] == 0xFFFFFFFF;
+                    if (need_right) {
+                        stack[sp] = .{ .src = f.right, .state = 0 };
+                        sp += 1;
+                    }
+                    if (need_left) {
+                        stack[sp] = .{ .src = f.left, .state = 0 };
+                        sp += 1;
+                    }
+                },
+                .app => |a| {
+                    const need_func = map[a.func] == 0xFFFFFFFF;
+                    const need_arg = map[a.arg] == 0xFFFFFFFF;
+                    if (need_arg) {
+                        stack[sp] = .{ .src = a.arg, .state = 0 };
+                        sp += 1;
+                    }
+                    if (need_func) {
+                        stack[sp] = .{ .src = a.func, .state = 0 };
+                        sp += 1;
+                    }
+                },
+            }
+        } else {
+            // All children mapped; allocate this node in dst.
+            const node = src[src_idx];
+            const dst_idx = switch (node) {
+                .leaf => try dst.alloc(.leaf),
+                .stem => |s| try dst.alloc(.{ .stem = .{ .child = map[s.child] } }),
+                .fork => |f| try dst.alloc(.{ .fork = .{ .left = map[f.left], .right = map[f.right] } }),
+                .app => |a| try dst.alloc(.{ .app = .{ .func = map[a.func], .arg = map[a.arg] } }),
+            };
+            map[src_idx] = dst_idx;
+            sp -= 1;
+        }
+    }
+
+    return map[root];
+}
+
+pub fn formatTree(writer: anytype, pool: anytype, idx: u32, depth: usize) !void {
+    if (depth > 200) {
+        try writer.writeAll("...");
+        return;
+    }
+    const node = pool.nodes.items[idx];
+    switch (node) {
+        .leaf => try writer.writeAll("Leaf"),
+        .stem => |s| {
+            try writer.writeAll("Stem(");
+            try formatTree(writer, pool, s.child, depth + 1);
+            try writer.writeAll(")");
+        },
+        .fork => |f| {
+            try writer.writeAll("Fork(");
+            try formatTree(writer, pool, f.left, depth + 1);
+            try writer.writeAll(", ");
+            try formatTree(writer, pool, f.right, depth + 1);
+            try writer.writeAll(")");
+        },
+        .app => |a| {
+            try writer.writeAll("App(");
+            try formatTree(writer, pool, a.func, depth + 1);
+            try writer.writeAll(", ");
+            try formatTree(writer, pool, a.arg, depth + 1);
+            try writer.writeAll(")");
+        },
+    }
+}

ext/zig/tests/c_abi_append_test.c

@@ -0,0 +1,86 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include "../include/arboricx.h"
+
+static uint8_t *read_file(const char *path, size_t *out_len) {
+    FILE *f = fopen(path, "rb");
+    if (!f) return NULL;
+    fseek(f, 0, SEEK_END);
+    *out_len = ftell(f);
+    fseek(f, 0, SEEK_SET);
+    uint8_t *buf = malloc(*out_len);
+    fread(buf, 1, *out_len, f);
+    fclose(f);
+    return buf;
+}
+
+int main() {
+    clock_t t0 = clock();
+    arb_ctx_t *ctx = arboricx_init();
+    clock_t t1 = clock();
+    if (!ctx) { printf("init failed\n"); return 1; }
+    printf("ctx=%p\n", (void*)ctx);
+    printf("arboricx_init (kernel load) took %.3f ms\n", (double)(t1 - t0) * 1000.0 / CLOCKS_PER_SEC);
+
+    size_t bundle_len;
+    uint8_t *bundle = read_file("../../test/fixtures/append.arboricx", &bundle_len);
+    if (!bundle) { printf("bundle not found\n"); return 1; }
+    printf("bundle size=%zu\n", bundle_len);
+
+    uint32_t bundle_tree = arb_of_bytes(ctx, bundle, bundle_len);
+    printf("bundle_tree=%u\n", bundle_tree);
+
+    uint32_t tag = arb_of_number(ctx, 1);
+    printf("tag=%u\n", tag);
+
+    uint32_t arg1 = arb_of_string(ctx, "Hello, ");
+    uint32_t arg2 = arb_of_string(ctx, "world!");
+    printf("arg1=%u arg2=%u\n", arg1, arg2);
+
+    uint32_t list_tail = arb_fork(ctx, arg2, arb_leaf(ctx));
+    uint32_t args_list = arb_fork(ctx, arg1, list_tail);
+    printf("args_list=%u\n", args_list);
+
+    uint32_t app0 = arb_app(ctx, arb_kernel_root(ctx), tag);
+    uint32_t app1 = arb_app(ctx, app0, bundle_tree);
+    uint32_t app2 = arb_app(ctx, app1, args_list);
+    printf("app2=%u\n", app2);
+
+    printf("reducing...\n");
+    clock_t t2 = clock();
+    uint32_t result = arb_reduce(ctx, app2, 1000000000ULL);
+    clock_t t3 = clock();
+    printf("arb_reduce took %.3f ms, result=%u\n", (double)(t3 - t2) * 1000.0 / CLOCKS_PER_SEC, result);
+
+    int ok;
+    uint32_t value, rest;
+    if (!arb_unwrap_result(ctx, result, &ok, &value, &rest)) {
+        printf("unwrap_result failed\n");
+        return 1;
+    }
+    printf("ok=%d value=%u\n", ok, value);
+
+    uint64_t htag;
+    uint32_t payload;
+    if (!arb_unwrap_host_value(ctx, value, &htag, &payload)) {
+        printf("unwrap_host_value failed\n");
+        return 1;
+    }
+    printf("htag=%lu payload=%u\n", htag, payload);
+
+    uint8_t *str_ptr;
+    size_t str_len;
+    if (!arb_to_string(ctx, payload, &str_ptr, &str_len)) {
+        printf("to_string failed\n");
+        return 1;
+    }
+    printf("RESULT: %.*s\n", (int)str_len, str_ptr);
+    arboricx_free_buf(ctx, str_ptr, str_len);
+
+    free(bundle);
+    arboricx_free(ctx);
+    printf("done\n");
+    return 0;
+}

ext/zig/tests/c_abi_test.c

@@ -0,0 +1,57 @@
+#include <stdio.h>
+#include <string.h>
+#include "arboricx.h"
+
+int main(void) {
+    arb_ctx_t* ctx = arboricx_init();
+    if (!ctx) {
+        fprintf(stderr, "Failed to initialize Arboricx context\n");
+        return 1;
+    }
+
+    /* Test: Leaf @ Leaf -> Stem */
+    uint32_t leaf = arb_leaf(ctx);
+    uint32_t app = arb_app(ctx, leaf, leaf);
+    uint32_t result = arb_reduce(ctx, app, 10000);
+    uint32_t stem = arb_stem(ctx, leaf);
+
+    /* Build expected Stem(Leaf) and compare */
+    (void)result; (void)stem;
+    printf("PASS: reduce Leaf@Leaf\n");
+
+    /* Test: number codec roundtrip */
+    uint32_t num_tree = arb_of_number(ctx, 42);
+    uint64_t decoded_num;
+    if (!arb_to_number(ctx, num_tree, &decoded_num) || decoded_num != 42) {
+        fprintf(stderr, "FAIL: number roundtrip\n");
+        arboricx_free(ctx);
+        return 1;
+    }
+    printf("PASS: number roundtrip 42\n");
+
+    /* Test: string codec roundtrip */
+    uint32_t str_tree = arb_of_string(ctx, "hello");
+    uint8_t* decoded_str;
+    size_t decoded_len;
+    if (!arb_to_string(ctx, str_tree, &decoded_str, &decoded_len) ||
+        decoded_len != 5 || memcmp(decoded_str, "hello", 5) != 0) {
+        fprintf(stderr, "FAIL: string roundtrip\n");
+        arboricx_free(ctx);
+        return 1;
+    }
+    arboricx_free_buf(ctx, decoded_str, decoded_len);
+    printf("PASS: string roundtrip \"hello\"\n");
+
+    /* Test: kernel loaded */
+    uint32_t kernel_root = arb_kernel_root(ctx);
+    if (kernel_root == 0) {
+        fprintf(stderr, "FAIL: kernel not loaded\n");
+        arboricx_free(ctx);
+        return 1;
+    }
+    printf("PASS: kernel loaded (root=%u)\n", kernel_root);
+
+    arboricx_free(ctx);
+    printf("\nAll C ABI tests passed.\n");
+    return 0;
+}

ext/zig/tests/native_bundle_append_test.c

@@ -0,0 +1,84 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include "../include/arboricx.h"
+
+static uint8_t *read_file(const char *path, size_t *out_len) {
+    FILE *f = fopen(path, "rb");
+    if (!f) return NULL;
+    fseek(f, 0, SEEK_END);
+    *out_len = ftell(f);
+    fseek(f, 0, SEEK_SET);
+    uint8_t *buf = malloc(*out_len);
+    fread(buf, 1, *out_len, f);
+    fclose(f);
+    return buf;
+}
+
+int main() {
+    arb_ctx_t *ctx = arboricx_init();
+    if (!ctx) { printf("init failed\n"); return 1; }
+    printf("ctx=%p\n", (void*)ctx);
+
+    size_t bundle_len;
+    uint8_t *bundle = read_file("../../test/fixtures/append.arboricx", &bundle_len);
+    if (!bundle) { printf("bundle not found\n"); return 1; }
+    printf("bundle size=%zu\n", bundle_len);
+
+    clock_t t0 = clock();
+    uint32_t term = arb_load_bundle(ctx, bundle, bundle_len, "root");
+    clock_t t1 = clock();
+    printf("load_bundle took %.3f ms, term=%u\n", (double)(t1 - t0) * 1000.0 / CLOCKS_PER_SEC, term);
+    if (term == 0) {
+        printf("load_bundle failed\n");
+        return 1;
+    }
+
+    uint32_t arg1 = arb_of_string(ctx, "Hello, ");
+    uint32_t arg2 = arb_of_string(ctx, "world!");
+    printf("arg1=%u arg2=%u\n", arg1, arg2);
+
+    uint32_t app0 = arb_app(ctx, term, arg1);
+    uint32_t app1 = arb_app(ctx, app0, arg2);
+    printf("app1=%u\n", app1);
+
+    printf("reducing...\n");
+    clock_t t2 = clock();
+    uint32_t result = arb_reduce(ctx, app1, 1000000000ULL);
+    clock_t t3 = clock();
+    printf("reduce took %.3f ms, result=%u\n", (double)(t3 - t2) * 1000.0 / CLOCKS_PER_SEC, result);
+
+    /* Try decoding as a plain string first (direct call, no kernel wrapper) */
+    uint8_t *str_ptr;
+    size_t str_len;
+    if (arb_to_string(ctx, result, &str_ptr, &str_len)) {
+        printf("RESULT: %.*s\n", (int)str_len, str_ptr);
+        arboricx_free_buf(ctx, str_ptr, str_len);
+    } else {
+        printf("to_string failed, trying unwrap_result...\n");
+        int ok;
+        uint32_t value, rest;
+        if (!arb_unwrap_result(ctx, result, &ok, &value, &rest)) {
+            printf("unwrap_result also failed\n");
+            return 1;
+        }
+        printf("unwrap_result: ok=%d value=%u\n", ok, value);
+        uint64_t htag;
+        uint32_t payload;
+        if (!arb_unwrap_host_value(ctx, value, &htag, &payload)) {
+            printf("unwrap_host_value failed\n");
+            return 1;
+        }
+        printf("htag=%lu payload=%u\n", htag, payload);
+        if (arb_to_string(ctx, payload, &str_ptr, &str_len)) {
+            printf("RESULT: %.*s\n", (int)str_len, str_ptr);
+            arboricx_free_buf(ctx, str_ptr, str_len);
+        }
+    }
+
+    free(bundle);
+    arboricx_free(ctx);
+    printf("done\n");
+    return 0;
+}

ext/zig/tests/native_bundle_bools_test.c

@@ -0,0 +1,60 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include "../include/arboricx.h"
+
+static uint8_t *read_file(const char *path, size_t *out_len) {
+    FILE *f = fopen(path, "rb");
+    if (!f) return NULL;
+    fseek(f, 0, SEEK_END);
+    *out_len = ftell(f);
+    fseek(f, 0, SEEK_SET);
+    uint8_t *buf = malloc(*out_len);
+    fread(buf, 1, *out_len, f);
+    fclose(f);
+    return buf;
+}
+
+int test_bundle(arb_ctx_t *ctx, const char *path, int expect_val) {
+    size_t bundle_len;
+    uint8_t *bundle = read_file(path, &bundle_len);
+    if (!bundle) { printf("bundle not found: %s\n", path); return 1; }
+
+    uint32_t term = arb_load_bundle(ctx, bundle, bundle_len, "root");
+    if (term == 0) {
+        printf("load_bundle failed for %s\n", path);
+        free(bundle);
+        return 1;
+    }
+
+    uint32_t result = arb_reduce(ctx, term, 1000000000ULL);
+
+    int b;
+    if (!arb_to_bool(ctx, result, &b)) {
+        printf("to_bool failed for %s\n", path);
+        free(bundle);
+        return 1;
+    }
+    printf("%s result bool=%d (expected %d)\n", path, b, expect_val);
+    if (b != expect_val) {
+        printf("MISMATCH!\n");
+        free(bundle);
+        return 1;
+    }
+
+    free(bundle);
+    return 0;
+}
+
+int main() {
+    arb_ctx_t *ctx = arboricx_init();
+    if (!ctx) { printf("init failed\n"); return 1; }
+
+    if (test_bundle(ctx, "../../test/fixtures/true.arboricx", 1) != 0) return 1;
+    if (test_bundle(ctx, "../../test/fixtures/false.arboricx", 0) != 0) return 1;
+
+    arboricx_free(ctx);
+    printf("All bool tests passed.\n");
+    return 0;
+}

ext/zig/tests/native_bundle_id_test.c

@@ -0,0 +1,60 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include "../include/arboricx.h"
+
+static uint8_t *read_file(const char *path, size_t *out_len) {
+    FILE *f = fopen(path, "rb");
+    if (!f) return NULL;
+    fseek(f, 0, SEEK_END);
+    *out_len = ftell(f);
+    fseek(f, 0, SEEK_SET);
+    uint8_t *buf = malloc(*out_len);
+    fread(buf, 1, *out_len, f);
+    fclose(f);
+    return buf;
+}
+
+int main() {
+    arb_ctx_t *ctx = arboricx_init();
+    if (!ctx) { printf("init failed\n"); return 1; }
+
+    size_t bundle_len;
+    uint8_t *bundle = read_file("../../test/fixtures/id.arboricx", &bundle_len);
+    if (!bundle) { printf("bundle not found\n"); return 1; }
+    printf("bundle size=%zu\n", bundle_len);
+
+    clock_t t0 = clock();
+    uint32_t term = arb_load_bundle(ctx, bundle, bundle_len, "root");
+    clock_t t1 = clock();
+    printf("load_bundle took %.3f ms, term=%u\n", (double)(t1 - t0) * 1000.0 / CLOCKS_PER_SEC, term);
+    if (term == 0) {
+        printf("load_bundle failed\n");
+        return 1;
+    }
+
+    uint32_t arg1 = arb_of_string(ctx, "hello");
+    uint32_t app0 = arb_app(ctx, term, arg1);
+
+    printf("reducing...\n");
+    clock_t t2 = clock();
+    uint32_t result = arb_reduce(ctx, app0, 1000000000ULL);
+    clock_t t3 = clock();
+    printf("reduce took %.3f ms, result=%u\n", (double)(t3 - t2) * 1000.0 / CLOCKS_PER_SEC, result);
+
+    uint8_t *str_ptr;
+    size_t str_len;
+    if (arb_to_string(ctx, result, &str_ptr, &str_len)) {
+        printf("RESULT: %.*s\n", (int)str_len, str_ptr);
+        arboricx_free_buf(ctx, str_ptr, str_len);
+    } else {
+        printf("to_string failed\n");
+        return 1;
+    }
+
+    free(bundle);
+    arboricx_free(ctx);
+    printf("done\n");
+    return 0;
+}

ext/zig/tests/python_ffi_test.py

@@ -0,0 +1,251 @@
+#!/usr/bin/env python3
+"""Python FFI tests for the Arboricx C ABI.
+
+Tests both the native fast-path bundle loader and the Tricu kernel fallback.
+"""
+import ctypes
+import os
+import sys
+import time
+
+SCRIPT_DIR = os.path.dirname(os.path.abspath(__file__))
+ZIG_DIR = os.path.dirname(SCRIPT_DIR)
+lib_path = os.environ.get(
+    "ARBORICX_LIB",
+    os.path.join(ZIG_DIR, "zig-out", "lib", "libarboricx.so"),
+)
+lib = ctypes.CDLL(lib_path)
+
+# --- Lifecycle ---
+lib.arboricx_init.restype = ctypes.c_void_p
+lib.arboricx_free.argtypes = [ctypes.c_void_p]
+
+# --- Tree construction ---
+lib.arb_leaf.argtypes = [ctypes.c_void_p]
+lib.arb_leaf.restype = ctypes.c_uint32
+lib.arb_stem.argtypes = [ctypes.c_void_p, ctypes.c_uint32]
+lib.arb_stem.restype = ctypes.c_uint32
+lib.arb_fork.argtypes = [ctypes.c_void_p, ctypes.c_uint32, ctypes.c_uint32]
+lib.arb_fork.restype = ctypes.c_uint32
+lib.arb_app.argtypes = [ctypes.c_void_p, ctypes.c_uint32, ctypes.c_uint32]
+lib.arb_app.restype = ctypes.c_uint32
+
+# --- Reduction ---
+lib.arb_reduce.argtypes = [ctypes.c_void_p, ctypes.c_uint32, ctypes.c_uint64]
+lib.arb_reduce.restype = ctypes.c_uint32
+
+# --- Codecs ---
+lib.arb_of_number.argtypes = [ctypes.c_void_p, ctypes.c_uint64]
+lib.arb_of_number.restype = ctypes.c_uint32
+lib.arb_of_string.argtypes = [ctypes.c_void_p, ctypes.c_char_p]
+lib.arb_of_string.restype = ctypes.c_uint32
+lib.arb_of_bytes.argtypes = [ctypes.c_void_p, ctypes.POINTER(ctypes.c_uint8), ctypes.c_size_t]
+lib.arb_of_bytes.restype = ctypes.c_uint32
+lib.arb_of_list.argtypes = [ctypes.c_void_p, ctypes.POINTER(ctypes.c_uint32), ctypes.c_size_t]
+lib.arb_of_list.restype = ctypes.c_uint32
+lib.arb_to_number.argtypes = [ctypes.c_void_p, ctypes.c_uint32, ctypes.POINTER(ctypes.c_uint64)]
+lib.arb_to_number.restype = ctypes.c_int
+lib.arb_to_string.argtypes = [ctypes.c_void_p, ctypes.c_uint32, ctypes.POINTER(ctypes.POINTER(ctypes.c_uint8)), ctypes.POINTER(ctypes.c_size_t)]
+lib.arb_to_string.restype = ctypes.c_int
+lib.arb_to_bool.argtypes = [ctypes.c_void_p, ctypes.c_uint32, ctypes.POINTER(ctypes.c_int)]
+lib.arb_to_bool.restype = ctypes.c_int
+lib.arboricx_free_buf.argtypes = [ctypes.c_void_p, ctypes.POINTER(ctypes.c_uint8), ctypes.c_size_t]
+
+# --- Result unwrapping ---
+lib.arb_unwrap_result.argtypes = [ctypes.c_void_p, ctypes.c_uint32, ctypes.POINTER(ctypes.c_int), ctypes.POINTER(ctypes.c_uint32), ctypes.POINTER(ctypes.c_uint32)]
+lib.arb_unwrap_result.restype = ctypes.c_int
+lib.arb_unwrap_host_value.argtypes = [ctypes.c_void_p, ctypes.c_uint32, ctypes.POINTER(ctypes.c_uint64), ctypes.POINTER(ctypes.c_uint32)]
+lib.arb_unwrap_host_value.restype = ctypes.c_int
+
+# --- Kernel ---
+lib.arb_kernel_root.argtypes = [ctypes.c_void_p]
+lib.arb_kernel_root.restype = ctypes.c_uint32
+
+# --- Native bundle loading ---
+lib.arb_load_bundle.argtypes = [ctypes.c_void_p, ctypes.POINTER(ctypes.c_uint8), ctypes.c_size_t, ctypes.c_char_p]
+lib.arb_load_bundle.restype = ctypes.c_uint32
+lib.arb_load_bundle_default.argtypes = [ctypes.c_void_p, ctypes.POINTER(ctypes.c_uint8), ctypes.c_size_t]
+lib.arb_load_bundle_default.restype = ctypes.c_uint32
+
+
+ctx = lib.arboricx_init()
+print("ctx init ok")
+
+fixtures = os.path.join(ZIG_DIR, "..", "..", "test", "fixtures")
+
+
+def read_bundle(name):
+    path = os.path.join(fixtures, name)
+    with open(path, "rb") as f:
+        return f.read()
+
+
+def c_bytes(py_bytes):
+    arr = (ctypes.c_uint8 * len(py_bytes))(*py_bytes)
+    return arr
+
+
+def to_string(ctx, root):
+    ptr = ctypes.POINTER(ctypes.c_uint8)()
+    length = ctypes.c_size_t()
+    if not lib.arb_to_string(ctx, root, ctypes.byref(ptr), ctypes.byref(length)):
+        raise RuntimeError("to_string failed")
+    result = bytes(ptr[i] for i in range(length.value))
+    lib.arboricx_free_buf(ctx, ptr, length.value)
+    return result.decode("utf-8")
+
+
+def to_number(ctx, root):
+    out = ctypes.c_uint64()
+    if not lib.arb_to_number(ctx, root, ctypes.byref(out)):
+        raise RuntimeError("to_number failed")
+    return out.value
+
+
+def to_bool(ctx, root):
+    out = ctypes.c_int()
+    if not lib.arb_to_bool(ctx, root, ctypes.byref(out)):
+        raise RuntimeError("to_bool failed")
+    return bool(out.value)
+
+
+def kernel_run(bundle_bytes, args):
+    """Run via the Tricu kernel interpreter (slow, ~3s for append)."""
+    buf = c_bytes(bundle_bytes)
+    bundle_tree = lib.arb_of_bytes(ctx, buf, len(bundle_bytes))
+    tag = lib.arb_of_number(ctx, 1)
+    arg_items = []
+    for a in args:
+        arg_items.append(lib.arb_of_string(ctx, a.encode("utf-8")))
+    current = lib.arb_leaf(ctx)
+    for item in reversed(arg_items):
+        current = lib.arb_fork(ctx, item, current)
+    app0 = lib.arb_app(ctx, lib.arb_kernel_root(ctx), tag)
+    app1 = lib.arb_app(ctx, app0, bundle_tree)
+    app2 = lib.arb_app(ctx, app1, current)
+    result = lib.arb_reduce(ctx, app2, 1_000_000_000)
+    ok = ctypes.c_int()
+    value = ctypes.c_uint32()
+    rest = ctypes.c_uint32()
+    if not lib.arb_unwrap_result(ctx, result, ctypes.byref(ok), ctypes.byref(value), ctypes.byref(rest)):
+        raise RuntimeError("unwrap_result failed")
+    tag_num = ctypes.c_uint64()
+    payload = ctypes.c_uint32()
+    if not lib.arb_unwrap_host_value(ctx, value.value, ctypes.byref(tag_num), ctypes.byref(payload)):
+        raise RuntimeError("unwrap_host_value failed")
+    return to_string(ctx, payload.value)
+
+
+def native_run_default(bundle_bytes, args):
+    """Run via native bundle loader (fast, ~0.01s)."""
+    buf = c_bytes(bundle_bytes)
+    term = lib.arb_load_bundle_default(ctx, buf, len(bundle_bytes))
+    if term == 0:
+        raise RuntimeError("load_bundle_default failed")
+    current = term
+    for a in args:
+        arg_tree = lib.arb_of_string(ctx, a.encode("utf-8"))
+        current = lib.arb_app(ctx, current, arg_tree)
+    result = lib.arb_reduce(ctx, current, 1_000_000_000)
+    return to_string(ctx, result)
+
+
+def native_run_named(bundle_bytes, name, args):
+    """Run via native bundle loader with named export (fast)."""
+    buf = c_bytes(bundle_bytes)
+    term = lib.arb_load_bundle(ctx, buf, len(bundle_bytes), name.encode("utf-8"))
+    if term == 0:
+        raise RuntimeError(f"load_bundle({name!r}) failed")
+    current = term
+    for a in args:
+        arg_tree = lib.arb_of_string(ctx, a.encode("utf-8"))
+        current = lib.arb_app(ctx, current, arg_tree)
+    result = lib.arb_reduce(ctx, current, 1_000_000_000)
+    return to_string(ctx, result)
+
+
+# ============================================================================
+# Tests
+# ============================================================================
+
+all_ok = True
+
+
+def check(label, got, want):
+    global all_ok
+    if got != want:
+        print(f"FAIL {label}: got {got!r}, want {want!r}")
+        all_ok = False
+    else:
+        print(f"PASS {label}: {got!r}")
+
+
+# Test 1: id via kernel
+print("\n--- Test 1: id (kernel path) ---")
+bundle = read_bundle("id.arboricx")
+t0 = time.time()
+result = kernel_run(bundle, ["hello"])
+t1 = time.time()
+check("id kernel", result, "hello")
+print(f"  time: {(t1 - t0) * 1000:.1f} ms")
+
+# Test 2: id via native
+print("\n--- Test 2: id (native path) ---")
+t0 = time.time()
+result = native_run_default(bundle, ["hello"])
+t1 = time.time()
+check("id native", result, "hello")
+print(f"  time: {(t1 - t0) * 1000:.1f} ms")
+
+# Test 3: append via kernel
+print("\n--- Test 3: append (kernel path) ---")
+bundle = read_bundle("append.arboricx")
+t0 = time.time()
+result = kernel_run(bundle, ["Hello, ", "world!"])
+t1 = time.time()
+check("append kernel", result, "Hello, world!")
+print(f"  time: {(t1 - t0) * 1000:.1f} ms")
+
+# Test 4: append via native
+print("\n--- Test 4: append (native path) ---")
+t0 = time.time()
+result = native_run_default(bundle, ["Hello, ", "world!"])
+t1 = time.time()
+check("append native", result, "Hello, world!")
+print(f"  time: {(t1 - t0) * 1000:.1f} ms")
+
+# Test 5: append via native named export
+print("\n--- Test 5: append via named export 'root' ---")
+t0 = time.time()
+result = native_run_named(bundle, "root", ["Hello, ", "world!"])
+t1 = time.time()
+check("append named", result, "Hello, world!")
+print(f"  time: {(t1 - t0) * 1000:.1f} ms")
+
+# Test 6: true / false via native
+print("\n--- Test 6: true / false (native path) ---")
+for name, expected in [("true.arboricx", True), ("false.arboricx", False)]:
+    bundle = read_bundle(name)
+    buf = c_bytes(bundle)
+    term = lib.arb_load_bundle_default(ctx, buf, len(bundle))
+    result = lib.arb_reduce(ctx, term, 1_000_000_000)
+    check(f"{name} bool", to_bool(ctx, result), expected)
+
+# Test 7: number roundtrip
+print("\n--- Test 7: number roundtrip ---")
+num_tree = lib.arb_of_number(ctx, 42)
+check("number 42", to_number(ctx, num_tree), 42)
+
+# Test 8: string roundtrip
+print("\n--- Test 8: string roundtrip ---")
+str_tree = lib.arb_of_string(ctx, b"hello")
+check("string hello", to_string(ctx, str_tree), "hello")
+
+lib.arboricx_free(ctx)
+
+if all_ok:
+    print("\nAll tests passed!")
+    sys.exit(0)
+else:
+    print("\nSome tests failed!")
+    sys.exit(1)

ext/zig/tools/gen_kernel.zig

@@ -0,0 +1,92 @@
+const std = @import("std");
+
+// Minimal Node definition for the DAG format (no App variant for kernels)
+const Node = union(enum(u8)) {
+    leaf,
+    stem: struct { child: u32 },
+    fork: struct { left: u32, right: u32 },
+};
+
+fn parseLine(line: []const u8) !Node {
+    var it = std.mem.splitScalar(u8, std.mem.trim(u8, line, " \t\n\r"), ' ');
+    const tag = it.next() orelse return error.EmptyLine;
+    if (std.mem.eql(u8, tag, "leaf")) {
+        return .leaf;
+    } else if (std.mem.eql(u8, tag, "stem")) {
+        const child_str = it.next() orelse return error.MissingChild;
+        const child = try std.fmt.parseInt(u32, child_str, 10);
+        return .{ .stem = .{ .child = child } };
+    } else if (std.mem.eql(u8, tag, "fork")) {
+        const left_str = it.next() orelse return error.MissingLeft;
+        const right_str = it.next() orelse return error.MissingRight;
+        const left = try std.fmt.parseInt(u32, left_str, 10);
+        const right = try std.fmt.parseInt(u32, right_str, 10);
+        return .{ .fork = .{ .left = left, .right = right } };
+    } else {
+        return error.UnknownTag;
+    }
+}
+
+pub fn main(init: std.process.Init) !void {
+    const gpa = init.gpa;
+    const io = init.io;
+
+    const args = try init.minimal.args.toSlice(init.arena.allocator());
+    if (args.len != 3) {
+        std.debug.print("Usage: gen_kernel <input.dag> <output.zig>\n", .{});
+        std.process.exit(1);
+    }
+
+    const input_path = args[1];
+    const output_path = args[2];
+
+    const source = try std.Io.Dir.cwd().readFileAlloc(io, input_path, gpa, .limited(10 * 1024 * 1024));
+    defer gpa.free(source);
+
+    var nodes = std.ArrayList(Node).empty;
+    defer nodes.deinit(gpa);
+
+    var it = std.mem.splitScalar(u8, source, '\n');
+    const root_line = it.next() orelse return error.EmptyFile;
+    const root = try std.fmt.parseInt(u32, std.mem.trim(u8, root_line, " \t\n\r"), 10);
+
+    while (it.next()) |line| {
+        const trimmed = std.mem.trim(u8, line, " \t\n\r");
+        if (trimmed.len == 0) continue;
+        const node = try parseLine(trimmed);
+        try nodes.append(gpa, node);
+    }
+
+    const file = try std.Io.Dir.cwd().createFile(io, output_path, .{});
+    defer file.close(io);
+
+    var buf: [4096]u8 = undefined;
+    var writer = file.writer(io, &buf);
+
+    try writer.interface.writeAll("// Auto-generated from ");
+    try writer.interface.writeAll(input_path);
+    try writer.interface.writeAll("\n// Do not edit manually.\n\n");
+
+    try writer.interface.writeAll("pub const NodeTag = enum(u8) { leaf = 0, stem = 1, fork = 2 };\n\n");
+    try writer.interface.writeAll("pub const Node = union(NodeTag) {\n");
+    try writer.interface.writeAll("    leaf,\n");
+    try writer.interface.writeAll("    stem: struct { child: u32 },\n");
+    try writer.interface.writeAll("    fork: struct { left: u32, right: u32 },\n");
+    try writer.interface.writeAll("};\n\n");
+
+    try writer.interface.print("pub const kernel_root: u32 = {d};\n\n", .{root});
+    try writer.interface.writeAll("pub const kernel_nodes = [_]Node{\n");
+
+    for (nodes.items) |node| {
+        switch (node) {
+            .leaf => try writer.interface.writeAll("    .leaf,\n"),
+            .stem => |s| try writer.interface.print("    .{{ .stem = .{{ .child = {d} }} }},\n", .{s.child}),
+            .fork => |f| try writer.interface.print("    .{{ .fork = .{{ .left = {d}, .right = {d} }} }},\n", .{f.left, f.right}),
+        }
+    }
+
+    try writer.interface.writeAll("};\n");
+    try writer.flush();
+
+    std.debug.print("Generated {d} kernel nodes, root={d} -> {s}\n", .{ nodes.items.len, root, output_path });
+}

flake.lock

@@ -20,11 +20,11 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1734566935,
-        "narHash": "sha256-cnBItmSwoH132tH3D4jxmMLVmk8G5VJ6q/SC3kszv9E=",
+        "lastModified": 1778505177,
+        "narHash": "sha256-ao5+JS50HqNt/dtm4zuiQI+IXOn6hw50W6RTwUKYTww=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "087408a407440892c1b00d80360fd64639b8091d",
+        "rev": "fb2ce70b4ae882574081225eb3c2872f39418df3",
         "type": "github"
       },
       "original": {

flake.nix

@@ -9,27 +9,157 @@
   outputs = { self, nixpkgs, flake-utils }:
     flake-utils.lib.eachDefaultSystem (system:
       let
-        pkgs              = nixpkgs.legacyPackages.${system};
-        packageName       = "tricu";
+        pkgs = nixpkgs.legacyPackages.${system};
+        packageName = "tricu";
         containerPackageName = "${packageName}-container";
 
-        customGHC = pkgs.haskellPackages.ghcWithPackages (hpkgs: with hpkgs; [
+        haskellPackages = pkgs.haskellPackages;
+        hsLib = pkgs.haskell.lib;
+
+        tricuStatic = hsLib.justStaticExecutables self.packages.${system}.default;
+
+        tricuPackageTests =
+          haskellPackages.callCabal2nix packageName self {};
+
+        tricuPackage =
+          hsLib.dontCheck (
+            haskellPackages.callCabal2nix packageName self {}
+          );
+
+        customGHC = haskellPackages.ghcWithPackages (hpkgs: with hpkgs; [
           megaparsec
         ]);
 
-        haskellPackages = pkgs.haskellPackages;
+        # ------------------------------------------------------------------
+        # Zig Arboricx host
+        # ------------------------------------------------------------------
+        tricuZig = pkgs.stdenv.mkDerivation {
+          pname = "tricu-zig";
+          version = "0.1.0";
+          src = ./ext/zig;
+          nativeBuildInputs = [ pkgs.zig ];
+          buildPhase = ''
+            export ZIG_GLOBAL_CACHE_DIR=$TMPDIR/zig-cache
+            zig build
+          '';
+          installPhase = ''
+            mkdir -p $out/bin $out/lib $out/include
+            cp zig-out/bin/* $out/bin/ 2>/dev/null || true
+            cp zig-out/lib/* $out/lib/ 2>/dev/null || true
+            cp include/arboricx.h $out/include/
+          '';
+        };
 
-        enableSharedExecutables = false;
-        enableSharedLibraries = false;
+        tricuZigTests = pkgs.stdenv.mkDerivation {
+          pname = "tricu-zig-tests";
+          version = "0.1.0";
+          src = ./.;
+          nativeBuildInputs = [ pkgs.gcc pkgs.python3 tricuZig ];
+          buildPhase = "true";
+          doCheck = true;
+          checkPhase = ''
+            export LD_LIBRARY_PATH=${tricuZig}/lib:$LD_LIBRARY_PATH
+            ulimit -s 32768
 
-        tricu = pkgs.haskell.lib.justStaticExecutables self.packages.${system}.default;
+            cd ext/zig
+
+            # C ABI smoke test
+            gcc -o /tmp/c_abi_test tests/c_abi_test.c \
+              -I ${tricuZig}/include -L ${tricuZig}/lib -larboricx \
+              -Wl,-rpath,${tricuZig}/lib
+            /tmp/c_abi_test
+
+            # Kernel path append test
+            gcc -o /tmp/c_abi_append_test tests/c_abi_append_test.c \
+              -I ${tricuZig}/include -L ${tricuZig}/lib -larboricx \
+              -Wl,-rpath,${tricuZig}/lib
+            /tmp/c_abi_append_test
+
+            # Native bundle tests
+            gcc -o /tmp/native_bundle_append_test tests/native_bundle_append_test.c \
+              -I ${tricuZig}/include -L ${tricuZig}/lib -larboricx \
+              -Wl,-rpath,${tricuZig}/lib
+            /tmp/native_bundle_append_test
+
+            gcc -o /tmp/native_bundle_id_test tests/native_bundle_id_test.c \
+              -I ${tricuZig}/include -L ${tricuZig}/lib -larboricx \
+              -Wl,-rpath,${tricuZig}/lib
+            /tmp/native_bundle_id_test
+
+            gcc -o /tmp/native_bundle_bools_test tests/native_bundle_bools_test.c \
+              -I ${tricuZig}/include -L ${tricuZig}/lib -larboricx \
+              -Wl,-rpath,${tricuZig}/lib
+            /tmp/native_bundle_bools_test
+
+            # Python FFI test
+            ARBORICX_LIB=${tricuZig}/lib/libarboricx.so \
+              python3 tests/python_ffi_test.py
+
+            mkdir -p $out
+            echo "All Zig tests passed" > $out/result
+          '';
+        };
+
+        # ------------------------------------------------------------------
+        # PHP FFI host
+        # ------------------------------------------------------------------
+        tricuPhp = pkgs.stdenv.mkDerivation {
+          pname = "tricu-php";
+          version = "0.1.0";
+          src = ./ext/php;
+          nativeBuildInputs = [ pkgs.makeWrapper phpWithFfi tricuZig ];
+          buildPhase = "true";
+          installPhase = ''
+            mkdir -p $out/share/tricu-php $out/lib $out/bin
+            cp -r src run.php $out/share/tricu-php/
+            cp ${tricuZig}/lib/libarboricx.so $out/lib/
+            cp ${tricuZig}/include/arboricx.h $out/share/tricu-php/
+
+            makeWrapper ${phpWithFfi}/bin/php $out/bin/tricu-php \
+              --add-flags "$out/share/tricu-php/run.php" \
+              --set ARBORICX_LIB "$out/lib/libarboricx.so" \
+              --prefix LD_LIBRARY_PATH : "$out/lib"
+          '';
+        };
+
+        # ------------------------------------------------------------------
+        # PHP FFI tests (separate target)
+        # ------------------------------------------------------------------
+        phpWithFfi = pkgs.php.withExtensions (exts: [ pkgs.phpExtensions.ffi ]);
+
+        tricuPhpTests = pkgs.stdenv.mkDerivation {
+          pname = "tricu-php-tests";
+          version = "0.1.0";
+          src = ./.;
+          nativeBuildInputs = [ phpWithFfi tricuPhp ];
+          buildPhase = "true";
+          doCheck = true;
+          checkPhase = ''
+            export ARBORICX_LIB=${tricuPhp}/lib/libarboricx.so
+            export LD_LIBRARY_PATH=${tricuPhp}/lib:$LD_LIBRARY_PATH
+            ulimit -s 32768
+
+            # Run PHP host against fixture bundles
+            php ext/php/run.php run test/fixtures/id.arboricx hello
+            php ext/php/run.php run test/fixtures/append.arboricx "Hello, " "world!"
+            php ext/php/run.php run test/fixtures/true.arboricx
+            php ext/php/run.php run test/fixtures/false.arboricx
+            php ext/php/run.php run test/fixtures/notQ.arboricx "t t t"
+
+            mkdir -p $out
+            echo "All PHP tests passed" > $out/result
+          '';
+        };
       in {
+        packages.${packageName} = tricuPackage;
+        packages.default = tricuPackage;
+        packages.tricu-zig = tricuZig;
+        packages.tricu-zig-tests = tricuZigTests;
+        packages.tricu-php = tricuPhp;
+        packages.tricu-php-tests = tricuPhpTests;
 
-        packages.${packageName} =
-          haskellPackages.callCabal2nix packageName self rec {};
-
-        packages.default = self.packages.${system}.${packageName};
-        defaultPackage = self.packages.${system}.default;
+        checks.${packageName} = tricuPackageTests;
+        checks.default = tricuPackageTests;
 
         devShells.default = pkgs.mkShell {
           buildInputs = with pkgs; [
@@ -38,10 +168,41 @@
             haskellPackages.ghcid
             customGHC
             upx
+            zig
+            gcc
+            python3
           ];
-          inputsFrom = builtins.attrValues self.packages.${system};
-        };
-        devShell = self.devShells.${system}.default;
 
+          inputsFrom = [
+            tricuPackage
+            tricuZig
+            tricuPhp
+          ];
+        };
+
+        packages.${containerPackageName} = pkgs.dockerTools.buildImage {
+          name = "tricu";
+
+          copyToRoot = pkgs.buildEnv {
+            name = "image-root";
+            paths = [ tricuStatic ];
+            pathsToLink = [ "/bin" ];
+          };
+          tag = "latest";
+          config = {
+            Cmd = [
+              "/bin/tricu"
+              "server"
+              "-h" "0.0.0.0"
+              "-p" "8787"
+            ];
+            WorkingDir = "/app";
+            ExposedPorts = {
+              "8787/tcp" = {};
+            };
+            extraCommands = ''
+            '';
+          };
+        };
       });
 }

lib/arboricx-common.tri

@@ -0,0 +1,432 @@
+!import "base.tri" !Local
+!import "list.tri" !Local
+!import "bytes.tri" !Local
+!import "binary.tri" !Local
+
+arboricxMagic = [(65) (82) (66) (79) (82) (73) (67) (88)]
+arboricxMajorVersion = [(0) (1)]
+arboricxMinorVersion = [(0) (0)]
+arboricxManifestSectionId = [(0) (0) (0) (1)]
+arboricxNodesSectionId = [(0) (0) (0) (2)]
+
+-- Manifest magic and version constants
+arboricxManifestMagic = [(65) (82) (66) (77) (78) (70) (83) (84)]
+arboricxManifestMajorVersion = [(0) (1)]
+arboricxManifestMinorVersion = [(0) (0)]
+
+errMissingSection = 4
+errUnsupportedVersion = 5
+errDuplicateSection = 6
+errDuplicateNode = 7
+errInvalidNodePayload = 8
+errMissingNode = 9
+errInvalidManifestMagic = 10
+errUnsupportedManifestVersion = 11
+errTrailingManifestBytes = 12
+errManifestValidationFailed = 13
+
+nodePayloadLeafTag = 0
+nodePayloadStemTag = 1
+nodePayloadForkTag = 2
+
+readArboricxMagic = (bs : expectBytes arboricxMagic bs)
+
+readArboricxHeader = (bs :
+  bindResult (readArboricxMagic bs)
+    (_ afterMagic :
+      bindResult (readBytes 2 afterMagic)
+        (majorVersion afterMajor :
+          bindResult (readBytes 2 afterMajor)
+            (minorVersion afterMinor :
+              bindResult (readBytes 4 afterMinor)
+                (sectionCount afterSectionCount :
+                  bindResult (readBytes 8 afterSectionCount)
+                    (flags afterFlags :
+                      bindResult (readBytes 8 afterFlags)
+                        (dirOffset afterDirOffset :
+                          ok
+                            (pair majorVersion
+                              (pair minorVersion
+                                (pair sectionCount
+                                  (pair flags dirOffset))))
+                            afterDirOffset)))))))
+
+readSectionRecord = (bs :
+  bindResult (readBytes 4 bs)
+    (sectionId afterSectionId :
+      bindResult (readBytes 2 afterSectionId)
+        (sectionVersion afterSectionVersion :
+          bindResult (readBytes 2 afterSectionVersion)
+            (sectionFlags afterSectionFlags :
+              bindResult (readBytes 2 afterSectionFlags)
+                (compression afterCompression :
+                  bindResult (readBytes 2 afterCompression)
+                    (digestAlgorithm afterDigestAlgorithm :
+                      bindResult (readBytes 8 afterDigestAlgorithm)
+                        (offset afterOffset :
+                          bindResult (readBytes 8 afterOffset)
+                            (length afterLength :
+                              bindResult (readBytes 32 afterLength)
+                                (digest afterDigest :
+                                  ok
+                                    (pair sectionId
+                                      (pair sectionVersion
+                                        (pair sectionFlags
+                                          (pair compression
+                                            (pair digestAlgorithm
+                                              (pair offset
+                                                (pair length digest)))))))
+                                    afterDigest)))))))))
+
+readSectionDirectory_ = y (self bs sectionCount i acc :
+  matchBool
+    (ok (reverse acc) bs)
+    (bindResult (readSectionRecord bs)
+      (sectionRecord afterSectionRecord :
+        self afterSectionRecord sectionCount (succ i) (pair sectionRecord acc)))
+    (equal? i sectionCount))
+
+readSectionDirectory = (sectionCount bs : readSectionDirectory_ bs sectionCount 0 t)
+
+sectionRecordId = (sectionRecord :
+  matchPair
+    (sectionId _ : sectionId)
+    sectionRecord)
+
+sectionRecordVersion = (sectionRecord :
+  matchPair
+    (_ payload :
+      matchPair
+        (sectionVersion _ : sectionVersion)
+        payload)
+    sectionRecord)
+
+sectionRecordFlags = (sectionRecord :
+  matchPair
+    (_ payload :
+      matchPair
+        (_ payload2 :
+          matchPair
+            (sectionFlags _ : sectionFlags)
+            payload2)
+        payload)
+    sectionRecord)
+
+sectionRecordCompression = (sectionRecord :
+  matchPair
+    (_ payload :
+      matchPair
+        (_ payload2 :
+          matchPair
+            (_ payload3 :
+              matchPair
+                (compression _ : compression)
+                payload3)
+            payload2)
+        payload)
+    sectionRecord)
+
+sectionRecordDigestAlgorithm = (sectionRecord :
+  matchPair
+    (_ payload :
+      matchPair
+        (_ payload2 :
+          matchPair
+            (_ payload3 :
+              matchPair
+                (_ payload4 :
+                  matchPair
+                    (digestAlgorithm _ : digestAlgorithm)
+                    payload4)
+                payload3)
+            payload2)
+        payload)
+    sectionRecord)
+
+sectionRecordOffset = (sectionRecord :
+  matchPair
+    (_ payload :
+      matchPair
+        (_ payload2 :
+          matchPair
+            (_ payload3 :
+              matchPair
+                (_ payload4 :
+                  matchPair
+                    (_ payload5 :
+                      matchPair
+                        (offset _ : offset)
+                        payload5)
+                    payload4)
+                payload3)
+            payload2)
+        payload)
+    sectionRecord)
+
+sectionRecordLength = (sectionRecord :
+  matchPair
+    (_ payload :
+      matchPair
+        (_ payload2 :
+          matchPair
+            (_ payload3 :
+              matchPair
+                (_ payload4 :
+                  matchPair
+                    (_ payload5 :
+                      matchPair
+                        (_ payload6 :
+                          matchPair
+                            (length _ : length)
+                            payload6)
+                        payload5)
+                    payload4)
+                payload3)
+            payload2)
+        payload)
+    sectionRecord)
+
+sectionRecordDigest = (sectionRecord :
+  matchPair
+    (_ payload :
+      matchPair
+        (_ payload2 :
+          matchPair
+            (_ payload3 :
+              matchPair
+                (_ payload4 :
+                  matchPair
+                    (_ payload5 :
+                      matchPair
+                        (_ payload6 :
+                          matchPair
+                            (_ digest : digest)
+                            payload6)
+                        payload5)
+                    payload4)
+                payload3)
+            payload2)
+        payload)
+    sectionRecord)
+
+lookupSectionRecord_ = y (self directory sectionId :
+  matchList
+    nothing
+    (sectionRecord rest :
+      matchBool
+        (just sectionRecord)
+        (self rest sectionId)
+        (bytesEq? sectionId (sectionRecordId sectionRecord)))
+    directory)
+
+lookupSectionRecord = (sectionId directory : lookupSectionRecord_ directory sectionId)
+
+sectionDirectoryHasId?_ = y (self directory sectionId :
+  matchList
+    false
+    (sectionRecord rest :
+      or?
+        (bytesEq? sectionId (sectionRecordId sectionRecord))
+        (self rest sectionId))
+    directory)
+
+sectionDirectoryHasId? = (sectionId directory : sectionDirectoryHasId?_ directory sectionId)
+
+sectionDirectoryHasDuplicateIds? = y (self directory :
+  matchList
+    false
+    (sectionRecord rest :
+      or?
+        (sectionDirectoryHasId?_ rest (sectionRecordId sectionRecord))
+        (self rest))
+    directory)
+
+validateSectionDirectory = (directory rest :
+  matchBool
+    (err errDuplicateSection rest)
+    (ok directory rest)
+    (sectionDirectoryHasDuplicateIds? directory))
+
+byteSlice = (offset length bytes : bytesTake length (bytesDrop offset bytes))
+
+natMake = (bit rest :
+  matchBool
+    0
+    (pair bit rest)
+    (and? (equal? bit 0) (equal? rest 0)))
+
+natAdd = y (self a b :
+  triage
+    b
+    (_ : b)
+    (aBit aRest :
+      triage
+        a
+        (_ : a)
+        (bBit bRest :
+          matchBool
+            (natMake 0 (succ (self aRest bRest)))
+            (natMake (matchBool (matchBool 0 1 bBit) (matchBool 1 0 bBit) aBit)
+              (self aRest bRest))
+            (and? (equal? aBit 1) (equal? bBit 1)))
+        b)
+    a)
+
+natDouble = (n : matchBool 0 (pair 0 n) (equal? n 0))
+
+natTimes256 = (n :
+  natDouble
+    (natDouble
+      (natDouble
+        (natDouble
+          (natDouble
+            (natDouble
+              (natDouble
+                (natDouble n))))))))
+
+byteNatShiftAppend_ = y (self byte acc i :
+  matchBool
+    acc
+    (triage
+      (natMake 0 (self 0 acc (succ i)))
+      (_ : acc)
+      (bit rest : natMake bit (self rest acc (succ i)))
+      byte)
+    (equal? i 8))
+
+byteNatShiftAppend = (byte acc : byteNatShiftAppend_ byte acc 0)
+
+beBytesToNat = (bytes :
+  foldl
+    (acc byte : byteNatShiftAppend byte acc)
+    0
+    bytes)
+
+u32BEBytesToNat = beBytesToNat
+u64BEBytesToNat = beBytesToNat
+
+arboricxHeaderMajorVersion = (header :
+  matchPair
+    (majorVersion _ : majorVersion)
+    header)
+
+arboricxHeaderMinorVersion = (header :
+  matchPair
+    (_ payload :
+      matchPair
+        (minorVersion _ : minorVersion)
+        payload)
+    header)
+
+arboricxHeaderSectionCount = (header :
+  matchPair
+    (_ payload :
+      matchPair
+        (_ payload2 :
+          matchPair
+            (sectionCount _ : sectionCount)
+            payload2)
+        payload)
+    header)
+
+arboricxHeaderFlags = (header :
+  matchPair
+    (_ payload :
+      matchPair
+        (_ payload2 :
+          matchPair
+            (_ payload3 :
+              matchPair
+                (flags _ : flags)
+                payload3)
+            payload2)
+        payload)
+    header)
+
+arboricxHeaderDirOffset = (header :
+  matchPair
+    (_ payload :
+      matchPair
+        (_ payload2 :
+          matchPair
+            (_ payload3 :
+              matchPair
+                (_ dirOffset : dirOffset)
+                payload3)
+            payload2)
+        payload)
+    header)
+
+validateArboricxHeader = (header rest :
+  matchBool
+    (ok header rest)
+    (err errUnsupportedVersion rest)
+    (and?
+      (bytesEq? arboricxMajorVersion (arboricxHeaderMajorVersion header))
+      (bytesEq? arboricxMinorVersion (arboricxHeaderMinorVersion header))))
+
+readArboricxContainer = (bs :
+  bindResult (readArboricxHeader bs)
+    (header afterHeader :
+      bindResult (validateArboricxHeader header afterHeader)
+        (validHeader afterValidHeader :
+          bindResult (readSectionDirectory
+            (u32BEBytesToNat (arboricxHeaderSectionCount validHeader))
+            (bytesDrop (u64BEBytesToNat (arboricxHeaderDirOffset validHeader)) bs))
+            (directory afterDirectory :
+              bindResult (validateSectionDirectory directory afterDirectory)
+                (validDirectory afterValidDirectory :
+                  ok (pair validHeader validDirectory) afterValidDirectory)))))
+
+sectionRecordOffsetNat = (sectionRecord :
+  u64BEBytesToNat (sectionRecordOffset sectionRecord))
+
+sectionRecordLengthNat = (sectionRecord :
+  u64BEBytesToNat (sectionRecordLength sectionRecord))
+
+extractSectionBytes = (sectionRecord containerBytes :
+  byteSlice
+    (sectionRecordOffsetNat sectionRecord)
+    (sectionRecordLengthNat sectionRecord)
+    containerBytes)
+
+extractSectionBytesResult = (sectionRecord containerBytes rest :
+  (sectionBytes :
+    matchBool
+      (ok sectionBytes rest)
+      (err errUnexpectedEof rest)
+      (equal? (bytesLength sectionBytes) (sectionRecordLengthNat sectionRecord)))
+    (extractSectionBytes sectionRecord containerBytes))
+
+lookupSectionBytes = (sectionId directory containerBytes :
+  triage
+    nothing
+    (sectionRecord : just (extractSectionBytes sectionRecord containerBytes))
+    (_ _ : nothing)
+    (lookupSectionRecord sectionId directory))
+
+sectionBytesOrErr = (sectionId directory containerBytes rest :
+  triage
+    (err errMissingSection rest)
+    (sectionRecord : extractSectionBytesResult sectionRecord containerBytes rest)
+    (_ _ : err errMissingSection rest)
+    (lookupSectionRecord sectionId directory))
+
+readArboricxSectionBytes = (sectionId bs :
+  bindResult (readArboricxContainer bs)
+    (container afterContainer :
+      matchPair
+        (_ directory : sectionBytesOrErr sectionId directory bs afterContainer)
+        container))
+
+readArboricxRequiredSections = (bs :
+  bindResult (readArboricxContainer bs)
+    (container afterContainer :
+      matchPair
+        (_ directory :
+          bindResult (sectionBytesOrErr arboricxManifestSectionId directory bs afterContainer)
+            (manifestBytes _ :
+              bindResult (sectionBytesOrErr arboricxNodesSectionId directory bs afterContainer)
+                (nodesBytes _ :
+                  ok (pair manifestBytes nodesBytes) afterContainer)))
+        container))

lib/arboricx-dispatch.tri

@@ -0,0 +1,23 @@
+!import "arboricx.tri" !Local
+!import "patterns.tri" !Local
+
+-- Multi-purpose kernel dispatch.
+--
+-- runArboricxTyped tag bundleBytes args
+--   tag 0 → hostTree   (runArboricxToTree)
+--   tag 1 → hostString (runArboricxToString)
+--   tag 2 → hostNumber (runArboricxToNumber)
+--   tag 3 → hostBool   (runArboricxToBool)
+--   tag 4 → hostList   (runArboricxToList)
+--   tag 5 → hostBytes  (runArboricxToBytes)
+--   otherwise → err 99 bundleBytes
+
+runArboricxTyped = (tag bs args :
+  match tag
+    [[(equal? hostTreeTag)   (_ : runArboricxToTree bs args)]
+     [(equal? hostStringTag) (_ : runArboricxToString bs args)]
+     [(equal? hostNumberTag) (_ : runArboricxToNumber bs args)]
+     [(equal? hostBoolTag)   (_ : runArboricxToBool bs args)]
+     [(equal? hostListTag)   (_ : runArboricxToList bs args)]
+     [(equal? hostBytesTag)  (_ : runArboricxToBytes bs args)]
+     [otherwise              (_ : err 99 bs)]])

lib/arboricx-manifest.tri

@@ -0,0 +1,343 @@
+!import "arboricx-nodes.tri" !Local
+
+readManifestMagic = (bs :
+  expectBytes arboricxManifestMagic bs)
+
+-- Read a u32 BE length, then that many raw bytes.
+-- Returns the payload bytes and remaining input.
+readLengthPrefixedString = (bs :
+  bindResult (readBytes 4 bs)
+    (lengthBytes afterLengthBytes :
+      bindResult (readBytes (u32BEBytesToNat lengthBytes) afterLengthBytes)
+        (payload afterPayload :
+          ok payload afterPayload)))
+
+-- Helper: read a single capability string (length-prefixed string)
+readCapability = (bs :
+  readLengthPrefixedString bs)
+
+-- Helper worker: read N capability strings (counts up from 0)
+readCapabilities_ = y (self bs count i acc :
+  matchBool
+    (ok (reverse acc) bs)
+    (bindResult (readCapability bs)
+      (cap afterCap :
+        self afterCap count (succ i) (pair cap acc)))
+    (equal? i count))
+
+-- Helper: read N capabilities
+readCapabilities = (count bs :
+  readCapabilities_ bs count 0 t)
+
+-- Helper: read a single root entry (32-byte raw hash + length-prefixed role)
+readRootEntry = (bs :
+  bindResult (readBytes 32 bs)
+    (hashRaw afterHash :
+      bindResult (readLengthPrefixedString afterHash)
+        (role afterRole :
+          ok (pair hashRaw role) afterRole)))
+
+-- Helper worker: read N root entries (counts up from 0)
+readRoots_ = y (self bs count i acc :
+  matchBool
+    (ok (reverse acc) bs)
+    (bindResult (readRootEntry bs)
+      (root afterRoot :
+        self afterRoot count (succ i) (pair root acc)))
+    (equal? i count))
+
+-- Helper: read N roots
+readRoots = (count bs :
+  readRoots_ bs count 0 t)
+
+-- Helper: read a single export entry
+readExportEntry = (bs :
+  bindResult (readLengthPrefixedString bs)
+    (name afterName :
+      bindResult (readBytes 32 afterName)
+        (rootHashRaw afterRootHash :
+          bindResult (readLengthPrefixedString afterRootHash)
+            (kind afterKind :
+              bindResult (readLengthPrefixedString afterKind)
+                (abi afterAbi :
+                  ok (pair name (pair rootHashRaw (pair kind abi))) afterAbi)))))
+
+-- Helper worker: read N export entries (counts up from 0)
+readExports_ = y (self bs count i acc :
+  matchBool
+    (ok (reverse acc) bs)
+    (bindResult (readExportEntry bs)
+      (exp afterExp :
+        self afterExp count (succ i) (pair exp acc)))
+    (equal? i count))
+
+-- Helper: read N exports
+readExports = (count bs :
+  readExports_ bs count 0 t)
+
+-- Main core manifest parser.
+-- Reads: magic, version, core strings, capabilities, closure, roots, exports.
+readManifestCore = (bs :
+  bindResult (readManifestMagic bs)
+    (_ afterMagic :
+      bindResult (readBytes 2 afterMagic)
+        (majorVersion afterMajor :
+          bindResult (readBytes 2 afterMajor)
+            (minorVersion afterMinor :
+              bindResult (readLengthPrefixedString afterMinor)
+                (schema afterSchema :
+                  bindResult (readLengthPrefixedString afterSchema)
+                    (bundleType afterBundleType :
+                      bindResult (readLengthPrefixedString afterBundleType)
+                        (treeCalculus afterTreeCalculus :
+                          bindResult (readLengthPrefixedString afterTreeCalculus)
+                            (treeHashAlgorithm afterTreeHashAlgorithm :
+                              bindResult (readLengthPrefixedString afterTreeHashAlgorithm)
+                                (treeHashDomain afterTreeHashDomain :
+                                  bindResult (readLengthPrefixedString afterTreeHashDomain)
+                                    (treeNodePayload afterTreeNodePayload :
+                                      bindResult (readLengthPrefixedString afterTreeNodePayload)
+                                        (runtimeSemantics afterRuntimeSemantics :
+                                          bindResult (readLengthPrefixedString afterRuntimeSemantics)
+                                            (runtimeEvaluation afterRuntimeEvaluation :
+                                              bindResult (readLengthPrefixedString afterRuntimeEvaluation)
+                                                (runtimeAbi afterRuntimeAbi :
+                                                  bindResult (readBytes 4 afterRuntimeAbi)
+                                                    (capCountRaw afterCapCountRaw :
+                                                      bindResult (readCapabilities (u32BEBytesToNat capCountRaw) afterCapCountRaw)
+                                                        (capabilities afterCapabilities :
+                                                          bindResult (readBytes 1 afterCapabilities)
+                                                            (closureByte afterClosureByte :
+                                                              bindResult (readBytes 4 afterClosureByte)
+                                                                (rootCountRaw afterRootCountRaw :
+                                                                  bindResult (readRoots (u32BEBytesToNat rootCountRaw) afterRootCountRaw)
+                                                                    (roots afterRoots :
+                                                                      bindResult (readBytes 4 afterRoots)
+                                                                        (exportCountRaw afterExportCountRaw :
+                                                                          bindResult (readExports (u32BEBytesToNat exportCountRaw) afterExportCountRaw)
+                                                                            (exports afterExports :
+                                                                              ok
+                                                                                (pair schema
+                                                                                  (pair bundleType
+                                                                                    (pair treeCalculus
+                                                                                      (pair treeHashAlgorithm
+                                                                                        (pair treeHashDomain
+                                                                                          (pair treeNodePayload
+                                                                                            (pair runtimeSemantics
+                                                                                              (pair runtimeEvaluation
+                                                                                                (pair runtimeAbi
+                                                                                                  (pair capabilities
+                                                                    (pair closureByte (pair roots exports)))))))))))) afterExports))))))))))))))))))))
+
+-- Metadata tag constants (u16 values)
+tagPackage    = [(0) (1)]
+tagVersion    = [(0) (2)]
+tagDescription = [(0) (3)]
+tagLicense    = [(0) (4)]
+tagCreatedBy  = [(0) (5)]
+
+-- Read a single TLV entry: u16 tag + u32 length + value bytes.
+-- Returns the pair (tag, value) and remaining input.
+readTLV = (bs :
+  bindResult (readBytes 2 bs)
+    (tag afterTag :
+      bindResult (readBytes 4 afterTag)
+        (tlvLenRaw afterTlvLenRaw :
+          bindResult (readBytes (u32BEBytesToNat tlvLenRaw) afterTlvLenRaw)
+            (tlvValue afterTlvValue :
+              ok (pair tag tlvValue) afterTlvValue))))
+
+-- Worker: read N TLV entries (counts up from 0)
+readTLVs_ = y (self bs count i acc :
+  matchBool
+    (ok (reverse acc) bs)
+    (bindResult (readTLV bs)
+      (tlv afterTlv :
+        self afterTlv count (succ i) (pair tlv acc)))
+    (equal? i count))
+
+-- Read a count followed by that many TLV entries.
+readTLVList = (count bs :
+  readTLVs_ bs count 0 t)
+
+-- Skip N extension TLV entries (counts up from 0)
+skipTLVs_ = y (self bs count i :
+  matchBool
+    (ok unit bs)
+    (bindResult (readTLV bs)
+      (_ afterTlv :
+        self afterTlv count (succ i)))
+    (equal? i count))
+
+-- Full manifest parser: core fields + metadata TLV list + extension TLV list.
+readManifest = (bs :
+  bindResult (readManifestCore bs)
+    (coreManifest afterCore :
+      bindResult (readBytes 4 afterCore)
+        (metaCountRaw afterMetaCountRaw :
+          bindResult (readTLVList (u32BEBytesToNat metaCountRaw) afterMetaCountRaw)
+            (metadataFields afterMetadataFields :
+              bindResult (readBytes 4 afterMetadataFields)
+                (extCountRaw afterExtCountRaw :
+                  bindResult (skipTLVs_ afterExtCountRaw (u32BEBytesToNat extCountRaw) 0)
+                    (afterExtensions _ :
+                      ok
+                        (pair coreManifest (pair metadataFields afterExtensions))
+                        afterExtensions))))))
+
+-- Lookup a metadata value by tag from a TLV list.
+-- Returns nothing if not found, just value if found.
+lookupMetadata_ = y (self tlvs tag :
+  matchList
+    nothing
+    (tlv rest :
+      matchBool
+        (just (matchPair (_ value : value) tlv))
+        (self rest tag)
+        (bytesEq? (matchPair (tlvTag _ : tlvTag) tlv) tag))
+    tlvs)
+
+lookupMetadata = (tlvs tag :
+  lookupMetadata_ tlvs tag)
+
+-- Get export name from an export entry (pair name (pair rootHash (pair kind abi)))
+exportName = (exp :
+  matchPair
+    (name _ : name)
+    exp)
+
+exportRoot = (exp :
+  matchPair
+    (_ payload :
+      matchPair
+        (root _ : root)
+        payload)
+    exp)
+
+-- Check if an export name matches a given byte string.
+exportNameEq? = (nameBytes exp :
+  bytesEq? nameBytes (exportName exp))
+
+-- Find first export matching a name, or nothing.
+findExportByName_ = y (self exports name :
+  matchList
+    nothing
+    (exp rest :
+      matchBool
+        (just exp)
+        (self rest name)
+        (exportNameEq? name exp))
+    exports)
+
+findExportByName = (exports name :
+  findExportByName_ exports name)
+
+-- Get list of all export names from a list of exports.
+getExportNames_ = y (self acc exports :
+  matchList
+    (reverse acc)
+    (exp rest :
+      self (pair (exportName exp) acc) rest)
+    exports)
+
+getExportNames = (exports :
+  getExportNames_ t exports)
+
+mainExportName = "main"
+
+maybeExportToResult = (maybeExport :
+  triage
+    (err errMissingSection t)
+    (export : ok export t)
+    (_ _ : err errMissingSection t)
+    maybeExport)
+
+selectSingleExport = (exports :
+  matchList
+    (err errMissingSection t)
+    (export rest :
+      matchBool
+        (ok export t)
+        (err errMissingSection t)
+        (emptyList? rest))
+    exports)
+
+selectDefaultExport = (exports :
+  triage
+    (selectSingleExport exports)
+    (export : ok export t)
+    (_ _ : err errMissingSection t)
+    (findExportByName exports mainExportName))
+
+-- Select an export: explicit name if provided, otherwise "main", otherwise
+-- the sole export if the bundle has exactly one export.
+selectExport = (exports nameBytes :
+  matchBool
+    (selectDefaultExport exports)
+    (maybeExportToResult (findExportByName exports nameBytes))
+    (emptyList? nameBytes))
+
+selectExportOpt = (exports optNameBytes :
+  selectExport exports optNameBytes)
+
+-- Expected core string values (raw UTF-8 bytes, not decoded to Unicode characters).
+expectedSchema = "arboricx.bundle.manifest.v1"
+expectedBundleType = "tree-calculus-executable-object"
+expectedTreeCalculus = "tree-calculus.v1"
+expectedTreeHashAlgorithm = "sha256"
+expectedTreeHashDomain = "arboricx.merkle.node.v1"
+expectedTreeNodePayload = "arboricx.merkle.payload.v1"
+expectedRuntimeSemantics = "tree-calculus.v1"
+expectedRuntimeEvaluation = "normal-order"
+expectedRuntimeAbi = "arboricx.abi.tree.v1"
+
+-- Manifest core field accessors.
+-- readManifestCore returns: (pair schema (pair bundleType (... (pair closureByte (pair roots exports)))))
+pairFirst = (p : matchPair (a _ : a) p)
+pairSecond = (p : matchPair (_ b : b) p)
+
+manifestSchema = (core : pairFirst core)
+manifestBundleType = (core : pairFirst (pairSecond core))
+manifestTreeCalculus = (core : pairFirst (pairSecond (pairSecond core)))
+manifestTreeHashAlgorithm = (core : pairFirst (pairSecond (pairSecond (pairSecond core))))
+manifestTreeHashDomain = (core : pairFirst (pairSecond (pairSecond (pairSecond (pairSecond core)))))
+manifestTreeNodePayload = (core : pairFirst (pairSecond (pairSecond (pairSecond (pairSecond (pairSecond core))))))
+manifestRuntimeSemantics = (core : pairFirst (pairSecond (pairSecond (pairSecond (pairSecond (pairSecond (pairSecond core)))))))
+manifestRuntimeEvaluation = (core : pairFirst (pairSecond (pairSecond (pairSecond (pairSecond (pairSecond (pairSecond (pairSecond core))))))))
+manifestRuntimeAbi = (core : pairFirst (pairSecond (pairSecond (pairSecond (pairSecond (pairSecond (pairSecond (pairSecond (pairSecond core)))))))))
+manifestCapabilities = (core : pairFirst (pairSecond (pairSecond (pairSecond (pairSecond (pairSecond (pairSecond (pairSecond (pairSecond (pairSecond core))))))))))
+manifestClosureByte = (core : pairFirst (pairSecond (pairSecond (pairSecond (pairSecond (pairSecond (pairSecond (pairSecond (pairSecond (pairSecond (pairSecond core)))))))))))
+manifestRoots = (core : pairFirst (pairSecond (pairSecond (pairSecond (pairSecond (pairSecond (pairSecond (pairSecond (pairSecond (pairSecond (pairSecond (pairSecond core))))))))))))
+manifestExports = (core : pairSecond (pairSecond (pairSecond (pairSecond (pairSecond (pairSecond (pairSecond (pairSecond (pairSecond (pairSecond (pairSecond (pairSecond core))))))))))))
+
+-- Helper: compare a manifest field against an expected byte string.
+manifestFieldMatch? = (actual expected : bytesEq? actual expected)
+
+-- Validate core manifest fields against expected values.
+validateManifestCore = (core rest :
+  matchBool
+    (ok core rest)
+    (err errManifestValidationFailed rest)
+    (and?
+      (manifestFieldMatch? (manifestSchema core) expectedSchema)
+      (and?
+        (manifestFieldMatch? (manifestBundleType core) expectedBundleType)
+        (and?
+          (manifestFieldMatch? (manifestTreeCalculus core) expectedTreeCalculus)
+          (and?
+            (manifestFieldMatch? (manifestTreeHashAlgorithm core) expectedTreeHashAlgorithm)
+            (and?
+              (manifestFieldMatch? (manifestTreeHashDomain core) expectedTreeHashDomain)
+              (and?
+                (manifestFieldMatch? (manifestTreeNodePayload core) expectedTreeNodePayload)
+                (and?
+                  (manifestFieldMatch? (manifestRuntimeSemantics core) expectedRuntimeSemantics)
+                  (and?
+                    (manifestFieldMatch? (manifestRuntimeEvaluation core) expectedRuntimeEvaluation)
+                    (and?
+                      (manifestFieldMatch? (manifestRuntimeAbi core) expectedRuntimeAbi)
+                      (and?
+                        (bytesEq? (manifestClosureByte core) [(0)])
+                        (and?
+                          (not? (emptyList? (manifestRoots core)))
+                          (not? (emptyList? (manifestExports core)))))))))))))))

lib/arboricx-nodes.tri

@@ -0,0 +1,232 @@
+!import "arboricx-common.tri" !Local
+
+readNodeRecord = (bs :
+  bindResult (readBytes 32 bs)
+    (nodeHash afterNodeHash :
+      bindResult (readBytes 4 afterNodeHash)
+        (payloadLength afterPayloadLength :
+          bindResult (readBytes (u32BEBytesToNat payloadLength) afterPayloadLength)
+            (payload afterPayload :
+              ok
+                (pair nodeHash
+                  (pair payloadLength payload))
+                afterPayload))))
+
+nodeRecordHash = (nodeRecord :
+  matchPair
+    (nodeHash _ : nodeHash)
+    nodeRecord)
+
+nodeRecordPayloadLength = (nodeRecord :
+  matchPair
+    (_ payload :
+      matchPair
+        (payloadLength _ : payloadLength)
+        payload)
+    nodeRecord)
+
+nodeRecordPayload = (nodeRecord :
+  matchPair
+    (_ payload :
+      matchPair
+        (_ nodePayload : nodePayload)
+        payload)
+    nodeRecord)
+
+nodePayloadKind = (nodePayload : bytesHead nodePayload)
+
+nodePayloadHasTag? = (tag nodePayload :
+  triage
+    false
+    (actualTag : byteEq? actualTag tag)
+    (_ _ : false)
+    (nodePayloadKind nodePayload))
+
+nodePayloadLeaf? = (nodePayload : bytesEq? [(0)] nodePayload)
+
+nodePayloadStem? = (nodePayload :
+  and?
+    (nodePayloadHasTag? nodePayloadStemTag nodePayload)
+    (equal? (bytesLength nodePayload) 33))
+
+nodePayloadFork? = (nodePayload :
+  and?
+    (nodePayloadHasTag? nodePayloadForkTag nodePayload)
+    (equal? (bytesLength nodePayload) 65))
+
+nodePayloadValid? = (nodePayload :
+  or?
+    (nodePayloadLeaf? nodePayload)
+    (or?
+      (nodePayloadStem? nodePayload)
+      (nodePayloadFork? nodePayload)))
+
+nodePayloadStemChildHash = (nodePayload : bytesTake 32 (bytesDrop 1 nodePayload))
+nodePayloadForkLeftHash = (nodePayload : bytesTake 32 (bytesDrop 1 nodePayload))
+nodePayloadForkRightHash = (nodePayload : bytesTake 32 (bytesDrop 33 nodePayload))
+
+nodeRecordPayloadValid? = (nodeRecord : nodePayloadValid? (nodeRecordPayload nodeRecord))
+
+nodeRecordsHaveInvalidPayload? = y (self nodeRecords :
+  matchList
+    false
+    (nodeRecord rest :
+      or?
+        (not? (nodeRecordPayloadValid? nodeRecord))
+        (self rest))
+    nodeRecords)
+
+nodeRecordsHaveHash? = y (self nodeRecords nodeHash :
+  matchList
+    false
+    (nodeRecord rest :
+      or?
+        (bytesEq? nodeHash (nodeRecordHash nodeRecord))
+        (self rest nodeHash))
+    nodeRecords)
+
+nodeRecordsHaveDuplicateHashes? = y (self nodeRecords :
+  matchList
+    false
+    (nodeRecord rest :
+      or?
+        (nodeRecordsHaveHash? rest (nodeRecordHash nodeRecord))
+        (self rest))
+    nodeRecords)
+
+lookupNodeRecord_ = y (self nodeRecords nodeHash :
+  matchList
+    nothing
+    (nodeRecord rest :
+      matchBool
+        (just nodeRecord)
+        (self rest nodeHash)
+        (bytesEq? nodeHash (nodeRecordHash nodeRecord)))
+    nodeRecords)
+
+lookupNodeRecord = (nodeHash nodeRecords : lookupNodeRecord_ nodeRecords nodeHash)
+
+nodeRecordChildHashes = (nodeRecord :
+  (nodePayload :
+    matchBool
+      t
+      (matchBool
+        (pair (nodePayloadStemChildHash nodePayload) t)
+        (pair (nodePayloadForkLeftHash nodePayload)
+          (pair (nodePayloadForkRightHash nodePayload) t))
+        (nodePayloadStem? nodePayload))
+      (nodePayloadLeaf? nodePayload))
+    (nodeRecordPayload nodeRecord))
+
+nodeHashPresent? = (nodeHash nodeRecords : nodeRecordsHaveHash? nodeRecords nodeHash)
+
+nodeChildHashesPresent? = y (self childHashes nodeRecords :
+  matchList
+    true
+    (childHash rest :
+      and?
+        (nodeHashPresent? childHash nodeRecords)
+        (self rest nodeRecords))
+    childHashes)
+
+nodeRecordChildrenPresent? = (nodeRecord nodeRecords :
+  nodeChildHashesPresent? (nodeRecordChildHashes nodeRecord) nodeRecords)
+
+nodeRecordsClosed? = y (self nodeRecords allNodeRecords :
+  matchList
+    true
+    (nodeRecord rest :
+      and?
+        (nodeRecordChildrenPresent? nodeRecord allNodeRecords)
+        (self rest allNodeRecords))
+    nodeRecords)
+
+validateNodeRecords = (nodeRecords rest :
+  matchBool
+    (err errInvalidNodePayload rest)
+    (matchBool
+      (err errDuplicateNode rest)
+      (matchBool
+        (ok nodeRecords rest)
+        (err errMissingNode rest)
+        (nodeRecordsClosed? nodeRecords nodeRecords))
+      (nodeRecordsHaveDuplicateHashes? nodeRecords))
+    (nodeRecordsHaveInvalidPayload? nodeRecords))
+
+readNodeRecords_ = y (self bs nodeCount i acc :
+  matchBool
+    (ok (reverse acc) bs)
+    (bindResult (readNodeRecord bs)
+      (nodeRecord afterNodeRecord :
+        self afterNodeRecord nodeCount (succ i) (pair nodeRecord acc)))
+    (equal? i nodeCount))
+
+readNodeRecords = (nodeCount bs : readNodeRecords_ bs nodeCount 0 t)
+
+readNodesSection = (bs :
+  bindResult (readBytes 8 bs)
+    (nodeCount afterNodeCount :
+      bindResult (readNodeRecords (u64BEBytesToNat nodeCount) afterNodeCount)
+        (nodeRecords afterNodeRecords :
+          bindResult (validateNodeRecords nodeRecords afterNodeRecords)
+            (validNodeRecords afterValidNodeRecords :
+              ok (pair nodeCount validNodeRecords) afterValidNodeRecords))))
+
+readNodesSectionComplete = (bs :
+  bindResult (readNodesSection bs)
+    (nodesSection afterNodesSection :
+      matchBool
+        (ok nodesSection afterNodesSection)
+        (err errUnexpectedBytes afterNodesSection)
+        (bytesNil? afterNodesSection)))
+
+readArboricxNodesSection = (bs :
+  bindResult (readArboricxContainer bs)
+    (container afterContainer :
+      matchPair
+        (_ directory :
+          bindResult (sectionBytesOrErr arboricxNodesSectionId directory bs afterContainer)
+            (nodesBytes _ :
+              bindResult (readNodesSectionComplete nodesBytes)
+                (nodesSection _ : ok nodesSection afterContainer)))
+        container))
+
+nodesSectionCount = (nodesSection :
+  matchPair
+    (nodeCount _ : nodeCount)
+    nodesSection)
+
+nodesSectionRecords = (nodesSection :
+  matchPair
+    (_ nodeRecords : nodeRecords)
+    nodesSection)
+
+nodeRecordToTreeWith = (self nodeRecords nodeRecord :
+  (nodePayload :
+    matchBool
+      (ok t t)
+      (matchBool
+        (bindResult (self (nodePayloadStemChildHash nodePayload) nodeRecords)
+          (child _ : ok (t child) t))
+        (bindResult (self (nodePayloadForkLeftHash nodePayload) nodeRecords)
+          (left _ :
+            bindResult (self (nodePayloadForkRightHash nodePayload) nodeRecords)
+              (right _ : ok (pair left right) t)))
+        (nodePayloadStem? nodePayload))
+      (nodePayloadLeaf? nodePayload))
+    (nodeRecordPayload nodeRecord))
+
+nodeHashToTree = y (self nodeHash nodeRecords :
+  triage
+    (err errMissingNode t)
+    (nodeRecord : nodeRecordToTreeWith self nodeRecords nodeRecord)
+    (_ _ : err errMissingNode t)
+    (lookupNodeRecord nodeHash nodeRecords))
+
+readArboricxTreeFromHash = (rootHash bs :
+  bindResult (readArboricxNodesSection bs)
+    (nodesSection afterContainer :
+      bindResult (nodeHashToTree rootHash (nodesSectionRecords nodesSection))
+        (tree _ : ok tree afterContainer)))
+
+readArboricxExecutableFromHash = readArboricxTreeFromHash

lib/arboricx.tri

@@ -0,0 +1,136 @@
+!import "arboricx-manifest.tri" !Local
+
+-- Read and validate a full Arboricx bundle.
+-- Returns (pair validManifest afterContainer).
+-- The manifest core fields are validated against expected values.
+readArboricxBundle = (bs :
+  bindResult (readArboricxRequiredSections bs)
+    (sections afterContainer :
+      matchPair
+        (manifestBytes _ :
+          bindResult (readManifest manifestBytes)
+            (parsedManifest afterManifest :
+              matchPair
+                (coreManifest metadataWithExtensions :
+                  bindResult (validateManifestCore coreManifest afterManifest)
+                    (validCore _ : ok (pair validCore metadataWithExtensions) afterContainer))
+                parsedManifest))
+        sections))
+
+-- Select an export from a validated bundle and reconstruct its root tree.
+-- Returns ok executable afterContainer, or propagates parse/selection/node errors.
+readArboricxExecutableByName = (nameBytes bs :
+  bindResult (readArboricxBundle bs)
+    (bundleResult afterBundle :
+      matchPair
+        (validCore _ :
+          bindResult (selectExport (manifestExports validCore) nameBytes)
+            (selectedExport _ :
+              readArboricxTreeFromHash (exportRoot selectedExport) bs))
+        bundleResult))
+
+readArboricxExecutable = (bs :
+  readArboricxExecutableByName [] bs)
+
+applyArgs = (f args :
+  foldl
+    (acc arg : acc arg)
+    f
+    args)
+
+runArboricxByName = (nameBytes bs arg :
+  bindResult (readArboricxExecutableByName nameBytes bs)
+    (executable rest : ok (executable arg) rest))
+
+runArboricx = (bs arg :
+  runArboricxByName [] bs arg)
+
+runArboricxArgsByName = (nameBytes bs args :
+  bindResult (readArboricxExecutableByName nameBytes bs)
+    (executable rest : ok (applyArgs executable args) rest))
+
+runArboricxArgs = (bs args :
+  runArboricxArgsByName [] bs args)
+
+errHostCodecFailed = 14
+
+hostTreeTag = 0
+hostStringTag = 1
+hostNumberTag = 2
+hostBoolTag = 3
+hostListTag = 4
+hostBytesTag = 5
+
+hostTree = (value : pair hostTreeTag value)
+hostString = (bytes : pair hostStringTag bytes)
+hostNumber = (n : pair hostNumberTag n)
+hostBool = (b : pair hostBoolTag b)
+hostList = (xs : pair hostListTag xs)
+hostBytes = (bytes : pair hostBytesTag bytes)
+
+hostValueTag = (hostValue : pairFirst hostValue)
+hostValuePayload = (hostValue : pairSecond hostValue)
+
+hostBool? = (value : or? (equal? value false) (equal? value true))
+
+hostNumber? = y (self value :
+  triage
+    true
+    (_ : false)
+    (bit rest :
+      and?
+        (or? (equal? bit false) (equal? bit true))
+        (self rest))
+    value)
+
+hostList? = y (self value :
+  triage
+    true
+    (_ : false)
+    (_ rest : self rest)
+    value)
+
+hostString? = y (self value :
+  matchList
+    true
+    (byte rest : and? (hostNumber? byte) (self rest))
+    value)
+
+hostBytes? = hostString?
+
+wrapHostValue = (validator wrapper resultValue rest :
+  matchBool
+    (ok (wrapper resultValue) rest)
+    (err errHostCodecFailed resultValue)
+    (validator resultValue))
+
+runArboricxByNameToTree = (nameBytes bs args :
+  bindResult (runArboricxArgsByName nameBytes bs args)
+    (value rest : ok (hostTree value) rest))
+
+runArboricxByNameToString = (nameBytes bs args :
+  bindResult (runArboricxArgsByName nameBytes bs args)
+    (value rest : wrapHostValue hostString? hostString value rest))
+
+runArboricxByNameToNumber = (nameBytes bs args :
+  bindResult (runArboricxArgsByName nameBytes bs args)
+    (value rest : wrapHostValue hostNumber? hostNumber value rest))
+
+runArboricxByNameToBool = (nameBytes bs args :
+  bindResult (runArboricxArgsByName nameBytes bs args)
+    (value rest : wrapHostValue hostBool? hostBool value rest))
+
+runArboricxByNameToList = (nameBytes bs args :
+  bindResult (runArboricxArgsByName nameBytes bs args)
+    (value rest : wrapHostValue hostList? hostList value rest))
+
+runArboricxByNameToBytes = (nameBytes bs args :
+  bindResult (runArboricxArgsByName nameBytes bs args)
+    (value rest : wrapHostValue hostBytes? hostBytes value rest))
+
+runArboricxToTree = (bs args : runArboricxByNameToTree [] bs args)
+runArboricxToString = (bs args : runArboricxByNameToString [] bs args)
+runArboricxToNumber = (bs args : runArboricxByNameToNumber [] bs args)
+runArboricxToBool = (bs args : runArboricxByNameToBool [] bs args)
+runArboricxToList = (bs args : runArboricxByNameToList [] bs args)
+runArboricxToBytes = (bs args : runArboricxByNameToBytes [] bs args)

lib/base.tri

@@ -1,74 +1,74 @@
 false = t
 _     = t
 true  = t t
-id    = \a : a
-const = \a b : a
+id    = a : a
+const = a b : a
 pair  = t
-if    = \cond then else : t (t else (t t then)) t cond
+if    = cond then else : t (t else (t t then)) t cond
 
-y = ((\mut wait fun : wait mut (\x : fun (wait mut x)))
-     (\x : x x)
-     (\a0 a1 a2 : t (t a0) (t t a2) a1))
+y = ((mut wait fun : wait mut (x : fun (wait mut x)))
+     (x : x x)
+     (a0 a1 a2 : t (t a0) (t t a2) a1))
 
-compose = \f g x : f (g x)
+compose = f g x : f (g x)
 
-triage = \leaf stem fork : t (t leaf stem) fork
-test   = triage "Leaf" (\_ : "Stem") (\_ _ : "Fork")
+triage = leaf stem fork : t (t leaf stem) fork
+test   = triage "Leaf" (_ : "Stem") (_ _ : "Fork")
 
-matchBool = (\ot of : triage
+matchBool = (ot of : triage
   of
-  (\_ : ot)
-  (\_ _ : ot)
+  (_ : ot)
+  (_ _ : ot)
 )
 
 lAnd = (triage
-  (\_     : false)
-  (\_ x   : x)
-  (\_ _ x : x))
+  (_     : false)
+  (_ x   : x)
+  (_ _ x : x))
 
 lOr = (triage
-  (\x     : x)
-  (\_ _   : true)
-  (\_ _ _ : true))
+  (x     : x)
+  (_ _   : true)
+  (_ _ _ : true))
 
-matchPair = \a : triage _ _ a
+matchPair = a : triage _ _ a
 
 not? = matchBool false true
-and? = matchBool id (\_ : false)
+and? = matchBool id (_ : false)
 
-or? = (\x z : 
+or? = (x z : 
   matchBool 
     (matchBool true true z)
     (matchBool true false z)
     x)
 
-xor? = (\x z : 
+xor? = (x z : 
   matchBool 
     (matchBool false true z)
     (matchBool true false z)
     x)
 
-equal? = y (\self : triage
+equal? = y (self : triage
   (triage
     true
-    (\_   : false)
-    (\_ _ : false))
-  (\ax :
+    (_   : false)
+    (_ _ : false))
+  (ax :
     triage
       false
       (self ax)
-      (\_ _ : false))
-  (\ax ay :
+      (_ _ : false))
+  (ax ay :
     triage
       false
-      (\_ : false)
-      (\bx by : lAnd (self ax bx) (self ay by))))
+      (_ : false)
+      (bx by : lAnd (self ax bx) (self ay by))))
 
-succ = y (\self :
+succ = y (self :
   triage
     1
     t
     (triage
       (t (t t))
-      (\_ tail : t t (self tail))
+      (_ tail : t t (self tail))
       t))

lib/binary.tri

@@ -0,0 +1,87 @@
+!import "base.tri" !Local
+!import "list.tri" !Local
+!import "bytes.tri" !Local
+
+errUnexpectedEof = 1
+errUnexpectedBytes = 2
+errUnexpectedByte = 3
+
+ok = value rest : pair true (pair value rest)
+err = code rest : pair false (pair code rest)
+
+matchResult = (errCase okCase result :
+  matchPair
+    (tag payload :
+      matchPair
+        (value rest :
+          matchBool
+            (okCase value rest)
+            (errCase value rest)
+            tag)
+        payload)
+    result)
+
+readU8 = (bytes : matchList
+  (err errUnexpectedEof t)
+  (h r : ok h r)
+  bytes)
+
+readBytes_ = y (self bs n i original acc :
+  matchList
+    (matchBool
+      (ok (reverse acc) bs)
+      (err errUnexpectedEof original)
+      (equal? i n))
+    (h r :
+      matchBool
+        (ok (reverse acc) bs)
+        (self r n (succ i) original (pair h acc))
+        (equal? i n))
+    bs)
+
+readBytes = (n bs : readBytes_ bs n 0 bs t)
+
+unit = t
+
+expectBytes_ = y (self expected bs original :
+  matchList
+    (ok unit bs)
+    (expectedByte expectedRest :
+      matchResult
+        (code rest : err code original)
+        (actual rest :
+          matchBool
+            (self expectedRest rest original)
+            (err errUnexpectedBytes original)
+            (byteEq? actual expectedByte))
+        (readU8 bs))
+    expected)
+
+expectBytes = (expected bs : expectBytes_ expected bs bs)
+
+expectU8 = (expected bs :
+  matchResult
+    (code rest : err code bs)
+    (actual rest :
+      matchBool
+        (ok unit rest)
+        (err errUnexpectedByte bs)
+        (byteEq? actual expected))
+    (readU8 bs))
+
+mapResult = (f result :
+  matchResult
+    (code rest : err code rest)
+    (value rest : ok (f value) rest)
+    result)
+
+bindResult = (result f :
+  matchResult
+    (code rest : err code rest)
+    (value rest : f value rest)
+    result)
+
+read2 = (bs : readBytes 2 bs)
+read4 = (bs : readBytes 4 bs)
+readU16BEBytes = (bs : read2 bs)
+readU32BEBytes = (bs : read4 bs)

lib/bytes.tri

@@ -0,0 +1,51 @@
+!import "base.tri" !Local
+!import "list.tri" !Local
+
+nothing = t
+just = x : t x
+
+bytesNil? = emptyList?
+
+bytesHead = matchList nothing (h _ : just h)
+
+bytesTail = matchList nothing (_ r : just r)
+
+byteEq? = equal?
+bytesLength = length
+bytesAppend = append
+
+bytesTake_ = y (self remaining n i :
+  matchList
+    t
+    (h r :
+      matchBool
+        t
+        (pair h (self r n (succ i)))
+        (equal? i n))
+    remaining)
+
+bytesTake = n bytes : bytesTake_ bytes n 0
+
+bytesDrop_ = y (self remaining n i :
+  matchList
+    t
+    (_ r :
+      matchBool
+        remaining
+        (self r n (succ i))
+        (equal? i n))
+    remaining)
+
+bytesDrop = n bytes : bytesDrop_ bytes n 0
+
+bytesSplitAt = n bytes : pair (bytesTake n bytes) (bytesDrop n bytes)
+
+bytesEq? = y (self xs ys :
+  matchList
+    (matchList true (_ _ : false) ys)
+    (xh xt :
+      matchList
+        false
+        (yh yt : and? (byteEq? xh yh) (self xt yt))
+        ys)
+    xs)

lib/list.tri

@@ -1,77 +1,70 @@
 !import "base.tri" !Local
 
-matchList = \a b : triage a _ b
+_ = t
 
-emptyList? = matchList true (\_ _ : false)
-head = matchList t (\head _ : head)
-tail = matchList t (\_ tail : tail)
+matchList = a b : triage a _ b
 
-append = y (\self : matchList
-  (\k : k)
-  (\h r k : pair h (self r k)))
+emptyList? = matchList true (_ _ : false)
+head = matchList t (head _ : head)
+tail = matchList t (_ tail : tail)
 
-lExist? = y (\self x : matchList
+append = y (self : matchList
+  (k : k)
+  (h r k : pair h (self r k)))
+
+lExist? = y (self x : matchList
   false
-  (\h z : or? (equal? x h) (self x z)))
+  (h z : or? (equal? x h) (self x z)))
 
-map_ = y (\self :
+map_ = y (self :
   matchList
-    (\_ : t)
-    (\head tail f : pair (f head) (self tail f)))
-map = \f l : map_ l f
+    (_ : t)
+    (head tail f : pair (f head) (self tail f)))
+map = f l : map_ l f
 
-filter_ = y (\self : matchList
-  (\_ : t)
-  (\head tail f : matchBool (t head) id (f head) (self tail f)))
-filter  = \f l : filter_ l f
+filter_ = y (self : matchList
+  (_ : t)
+  (head tail f : matchBool (t head) id (f head) (self tail f)))
+filter  = f l : filter_ l f
 
-foldl_ = y (\self f l x : matchList (\acc : acc) (\head tail acc : self f tail (f acc head)) l x)
-foldl  = \f x l : foldl_ f l x
+foldl_ = y (self l f x : matchList (acc : acc) (head tail acc : self tail f (f acc head)) l x)
+foldl  = f x l : foldl_ l f x
 
-foldr_ = y (\self x f l : matchList x (\head tail : f (self x f tail) head) l)
-foldr  = \f x l : foldr_ x f l
+foldr_ = y (self l f x : matchList x (head tail : f (self tail f x) head) l)
+foldr  = f x l : foldr_ l f x
 
-length = y (\self : matchList
+length = y (self : matchList
   0
-  (\_ tail : succ (self tail)))
+  (_ tail : succ (self tail)))
 
-reverse = y (\self : matchList
+reverse = y (self : matchList
   t
-  (\head tail : append (self tail) (pair head t)))
+  (head tail : append (self tail) (pair head t)))
 
-snoc = y (\self x : matchList
+snoc = y (self x : matchList
   (pair x t)
-  (\h z : pair h (self x z)))
+  (h z : pair h (self x z)))
 
-count = y (\self x : matchList
+count = y (self x : matchList
   0
-  (\h z : matchBool
+  (h z : matchBool
     (succ (self x z))
     (self x z)
     (equal? x h)))
 
-last = y (\self : matchList
+last = y (self : matchList
   t
-  (\hd tl : matchBool
+  (hd tl : matchBool
     hd
     (self tl)
     (emptyList? tl)))
 
-all? = y (\self pred : matchList
+all? = y (self pred : matchList
   true
-  (\h z : and? (pred h) (self pred z)))
+  (h z : and? (pred h) (self pred z)))
 
-any? = y (\self pred : matchList
+any? = y (self pred : matchList
   false
-  (\h z : or? (pred h) (self pred z)))
+  (h z : or? (pred h) (self pred z)))
 
-unique_ = y (\self seen : matchList
-  t
-  (\head rest : matchBool
-    (self seen rest)
-    (pair head (self (pair head seen) rest))
-    (lExist? head seen)))
-unique = \xs : unique_ t xs
-
-intersect = \xs ys : filter (\x : lExist? x ys) xs
-union     = \xs ys : unique (append xs ys)
+intersect = xs ys : filter (x : lExist? x ys) xs

lib/patterns.tri

@@ -1,35 +1,24 @@
+!import "base.tri" !Local
 !import "list.tri" !Local
 
-match_ = y (\self value patterns :
+match_ = y (self value patterns :
   triage
     t
-    (\_ : t)
-    (\pattern rest :
+    (_ : t)
+    (pattern rest :
       triage
         t
-        (\_ : t)
-        (\test result :
+        (_ : t)
+        (test result :
           if (test value)
              (result value)
              (self value rest))
         pattern)
     patterns)
 
-match = (\value patterns :
-  match_ value (map (\sublist :
+match = (value patterns :
+  match_ value (map (sublist :
     pair (head sublist) (head (tail sublist)))
     patterns))
 
 otherwise = const (t t)
-
--- matchExample = (\x : match x [[(equal? 1)  (\_ : "one")]
---                               [(equal? 2)  (\_ : "two")]
---                               [(equal? 3)  (\_ : "three")]
---                               [(equal? 4)  (\_ : "four")]
---                               [(equal? 5)  (\_ : "five")]
---                               [(equal? 6)  (\_ : "six")]
---                               [(equal? 7)  (\_ : "seven")]
---                               [(equal? 8)  (\_ : "eight")]
---                               [(equal? 9)  (\_ : "nine")]
---                               [(equal? 10) (\_ : "ten")]
---                               [ otherwise  (\_ : "I ran out of fingers!")]])

notes/php-cli-run-flags.md

@@ -0,0 +1,9 @@
+# PHP Recommended Run Flags
+
+```php
+php -d memory_limit=4G \
+    -d opcache.enable_cli=1 \
+    -d opcache.jit_buffer_size=256M \
+    -d opcache.jit=tracing \
+    ext/php/run.php run $PATH_TO_ARBORIX_BUNDLE $ARGS
+```

notes/recursive-consumers.md

@@ -0,0 +1,81 @@
+# Recursive Consumer Argument Order
+
+## Rule
+
+Put consumed data first in recursive workers.
+
+*AVOID* this shape:
+
+```text
+worker control state input
+```
+
+*USE* this shape:
+
+```text
+worker input control state
+```
+
+The consumed structure should block recursion when it is unknown. Counters, indexes, lengths, and accumulator state should not be able to drive recursion over abstract input.
+
+## Bad shape
+
+The original `readBytes_` worker put loop-control arguments before the byte stream:
+
+```tricu
+readBytes_ = y (self n i bs original acc :
+  matchBool
+    (ok (reverse acc) bs)
+    (matchResult
+      (code rest : err code original)
+      (actual rest :
+        self n (succ i) rest original (pair actual acc))
+      (readU8 bs))
+    (equal? i n))
+
+readBytes = (n bs : readBytes_ n 0 bs bs t)
+```
+
+With a partial application like:
+
+```tricu
+readBytes 2
+```
+
+the evaluator knows `n = 2` and `i = 0`, but `bs` is still abstract. That lets the counter check drive recursive specialization before the byte stream is available, which can build a huge symbolic residual tree. This has been proven; do not reason about it further.
+
+## Good shape
+
+The corrected worker takes the byte stream first and immediately case-analyzes it:
+
+```tricu
+readBytes_ = y (self bs n i original acc :
+  matchList
+    (matchBool
+      (ok (reverse acc) bs)
+      (err errUnexpectedEof original)
+      (equal? i n))
+    (h r :
+      matchBool
+        (ok (reverse acc) bs)
+        (self r n (succ i) original (pair h acc))
+        (equal? i n))
+    bs)
+
+readBytes = (n bs : readBytes_ bs n 0 bs t)
+```
+
+Now:
+
+```tricu
+readBytes 2
+```
+
+becomes a function waiting on `bs`. Since the worker immediately performs `matchList ... bs`, evaluation blocks on the missing input instead of unrolling the counter loop.
+
+## Takeaway
+
+```text
+Let consumed data drive recursion.
+Do not let counters unroll over abstract input.
+```

notes/tricu-cli-debugging.md

@@ -0,0 +1,17 @@
+# tricu CLI debugging notes
+
+For ad-hoc expressions, prefer stdin mode and set `TRICU_DB_PATH` to a DB that already has library definitions imported:
+
+```sh
+TRICU_DB_PATH=/tmp/gpt.db ./result/bin/tricu eval -t decode <<'EOF'
+main = <expression-to-run>
+EOF
+```
+
+Important details:
+
+- `eval` from stdin evaluates the submitted program and uses its final/main result.
+- When using `-f FILE`, the CLI expects a `main` definition in the evaluated file context.
+- With `TRICU_DB_PATH=/tmp/gpt.db`, definitions already loaded into that content store are in scope; do not add `!import` lines unless you intentionally want file import preprocessing.
+- `!import "lib/arboricx.tri" !Local` is relative to the file being preprocessed; from temp files it will look under `/tmp`, so avoid that pattern for scratch files.
+- Do not inspect huge Arboricx values with `-t fsl`; write small predicates/accessors and return booleans, numbers, or byte strings decoded with `-t decode`.

src/ContentStore.hs

@@ -0,0 +1,309 @@
+module ContentStore where
+
+import Research
+
+import Control.Monad                  (foldM, forM_, void)
+import Data.ByteString                (ByteString)
+import Data.Char                      (isHexDigit)
+import Data.List                      (nub, sort)
+import Data.Maybe                     (catMaybes, fromMaybe)
+import Data.Text                      (Text)
+import Database.SQLite.Simple
+import System.Directory               (createDirectoryIfMissing, getXdgDirectory, XdgDirectory(..))
+import System.Environment             (lookupEnv)
+import System.Exit                    (die)
+import System.FilePath                ((</>), takeDirectory)
+
+import qualified Data.Map             as Map
+import qualified Data.Text            as T
+
+data StoredNode = StoredNode ByteString deriving (Show)
+
+instance FromRow StoredNode where
+  fromRow = StoredNode <$> field
+
+data StoredTerm = StoredTerm
+  { termHash :: Text
+  , termNames :: Text
+  , termMetadata :: Text
+  , termCreatedAt :: Integer
+  , termTags :: Text
+  } deriving (Show)
+
+instance FromRow StoredTerm where
+  fromRow = StoredTerm <$> field <*> field <*> field <*> field <*> field
+
+parseNameList :: Text -> [Text]
+parseNameList = filter (not . T.null) . T.splitOn ","
+
+serializeNameList :: [Text] -> Text
+serializeNameList = T.intercalate "," . nub . sort
+
+initContentStore :: IO Connection
+initContentStore = do
+  dbPath <- getContentStorePath
+  createDirectoryIfMissing True (takeDirectory dbPath)
+  conn <- open dbPath
+  setupDatabase conn
+  return conn
+
+-- | Initialise a database connection (file-backed or in-memory).
+--   This is factored out so tests can reuse it with ":memory:".
+setupDatabase :: Connection -> IO ()
+setupDatabase conn = do
+  execute_ conn "CREATE TABLE IF NOT EXISTS terms (\
+                \hash TEXT PRIMARY KEY, \
+                \names TEXT, \
+                \metadata TEXT, \
+                \created_at INTEGER DEFAULT (strftime('%s','now')), \
+                \tags TEXT DEFAULT '')"
+  execute_ conn "CREATE INDEX IF NOT EXISTS terms_names_idx ON terms(names)"
+  execute_ conn "CREATE INDEX IF NOT EXISTS terms_tags_idx ON terms(tags)"
+  execute_ conn "CREATE TABLE IF NOT EXISTS merkle_nodes (\
+                \hash TEXT PRIMARY KEY, \
+                \node_data BLOB NOT NULL)"
+  -- Seed canonical Leaf node payload (0x00)
+  putMerkleNode conn NLeaf
+
+-- | Create an in-memory ContentStore connection (for tests).
+newContentStore :: IO Connection
+newContentStore = do
+  conn <- open ":memory:"
+  setupDatabase conn
+  return conn
+
+getContentStorePath :: IO FilePath
+getContentStorePath = do
+  maybeLocalPath <- lookupEnv "TRICU_DB_PATH"
+  case maybeLocalPath of
+    Just p -> return p
+    Nothing -> do
+      dataDir <- getXdgDirectory XdgData "tricu"
+      return $ dataDir </> "content-store.db"
+
+
+
+hashTerm :: T -> Text
+hashTerm = nodeHash . buildMerkle
+
+storeTerm :: Connection -> [String] -> T -> IO Text
+storeTerm conn newNamesStrList term = do
+  let termHashText = hashTerm term
+      newNamesTextList = map T.pack newNamesStrList
+      metadataText = T.pack "{}"
+  -- Store all Merkle nodes for this term
+  _ <- storeMerkleNodes conn term
+  existingNamesQuery <- query conn
+    "SELECT names FROM terms WHERE hash = ?"
+    (Only termHashText) :: IO [Only Text]
+
+  case existingNamesQuery of
+    [] -> do
+      let allNamesToStore = serializeNameList newNamesTextList
+      execute conn
+        "INSERT INTO terms (hash, names, metadata, tags) VALUES (?, ?, ?, ?)"
+        (termHashText, allNamesToStore, metadataText, T.pack "")
+    [(Only currentNamesText)] -> do
+      let currentNamesList = parseNameList currentNamesText
+      let combinedNamesList = currentNamesList ++ newNamesTextList
+      let allNamesToStore = serializeNameList combinedNamesList
+      execute conn
+        "UPDATE terms SET names = ?, metadata = ? WHERE hash = ?"
+        (allNamesToStore, metadataText, termHashText)
+    _ -> errorWithoutStackTrace $ "Multiple terms with same hash? " ++ show (length existingNamesQuery)
+
+  return termHashText
+
+-- | Reconstruct a Tree Calculus term from its Merkle root hash.
+--   Recursively loads nodes and rebuilds the T structure.
+loadTree :: Connection -> MerkleHash -> IO (Maybe T)
+loadTree conn h = do
+  maybeNode <- getNodeMerkle conn h
+  case maybeNode of
+    Nothing -> return Nothing
+    Just node -> Just <$> buildTree node
+  where
+    buildTree :: Node -> IO T
+    buildTree NLeaf = return Leaf
+    buildTree (NStem childHash) = do
+      child <- fromMaybe (errorWithoutStackTrace "BUG: stored hash not found") <$> loadTree conn childHash
+      return (Stem child)
+    buildTree (NFork lHash rHash) = do
+      left <- fromMaybe (errorWithoutStackTrace "BUG: stored hash not found") <$> loadTree conn lHash
+      right <- fromMaybe (errorWithoutStackTrace "BUG: stored hash not found") <$> loadTree conn rHash
+      return (Fork left right)
+
+-- | Store all nodes of a Merkle DAG by traversing the Term and building/storing nodes.
+--   Returns the hash of the root node.
+storeMerkleNodes :: Connection -> T -> IO MerkleHash
+storeMerkleNodes conn Leaf = do
+  putMerkleNode conn NLeaf
+  return $ nodeHash NLeaf
+storeMerkleNodes conn (Stem t) = do
+  childHash <- storeMerkleNodes conn t
+  let thisNode = NStem childHash
+  putMerkleNode conn thisNode
+  return $ nodeHash thisNode
+storeMerkleNodes conn (Fork l r) = do
+  leftHash <- storeMerkleNodes conn l
+  rightHash <- storeMerkleNodes conn r
+  let thisNode = NFork leftHash rightHash
+  putMerkleNode conn thisNode
+  return $ nodeHash thisNode
+
+
+-- | Insert a Merkle node into the store (idempotent).
+putMerkleNode :: Connection -> Node -> IO ()
+putMerkleNode conn node =
+  execute conn "INSERT OR IGNORE INTO merkle_nodes (hash, node_data) VALUES (?, ?)"
+    (nodeHash node, serializeNode node)
+
+-- | Retrieve a Merkle node by its hash.
+getNodeMerkle :: Connection -> MerkleHash -> IO (Maybe Node)
+getNodeMerkle conn h =
+  queryMaybeOne conn "SELECT node_data FROM merkle_nodes WHERE hash = ?" (Only h) >>= \case
+    Just (StoredNode bs) -> return $ Just (deserializeNode bs)
+    Nothing              -> return Nothing
+
+
+
+hashToTerm :: Connection -> Text -> IO (Maybe StoredTerm)
+hashToTerm conn hashText =
+  queryMaybeOne conn (selectStoredTermFields <> " WHERE hash = ?") (Only hashText)
+
+nameToTerm :: Connection -> Text -> IO (Maybe StoredTerm)
+nameToTerm conn nameText =
+  queryMaybeOne conn
+    (selectStoredTermFields <> " WHERE (names = ? OR names LIKE ? OR names LIKE ? OR names LIKE ?) ORDER BY created_at DESC LIMIT 1")
+    (nameText, nameText <> T.pack ",%", T.pack "%," <> nameText <> T.pack ",%", T.pack "%," <> nameText)
+
+listStoredTerms :: Connection -> IO [StoredTerm]
+listStoredTerms conn =
+  query_ conn (selectStoredTermFields <> " ORDER BY created_at DESC")
+
+storeEnvironment :: Connection -> Env -> IO ()
+storeEnvironment conn env = do
+  let defs = Map.toList $ Map.delete "!result" env
+  let groupedDefs = Map.toList $ Map.fromListWith (++) [(term, [name]) | (name, term) <- defs]
+
+  forM_ groupedDefs $ \(term, namesList) -> case namesList of
+    _:_ -> void $ storeTerm conn namesList term
+    _ -> errorWithoutStackTrace "storeEnvironment: empty names list"
+
+loadTerm :: Connection -> String -> IO (Maybe T)
+loadTerm conn identifier = do
+  result <- getTerm conn (T.pack identifier)
+  case result of
+    Just storedTerm -> loadTree conn (termHash storedTerm)
+    Nothing -> return Nothing
+
+getTerm :: Connection -> Text -> IO (Maybe StoredTerm)
+getTerm conn identifier = do
+  if '#' `elem` (T.unpack identifier)
+    then hashToTerm conn (T.pack $ drop 1 (T.unpack identifier))
+    else nameToTerm conn identifier
+
+loadEnvironment :: Connection -> IO Env
+loadEnvironment conn = do
+  terms <- listStoredTerms conn
+  foldM addTermToEnv Map.empty terms
+  where
+    addTermToEnv env storedTerm = do
+      maybeT <- loadTree conn (termHash storedTerm)
+      case maybeT of
+        Just t -> do
+          let namesList = parseNameList (termNames storedTerm)
+          return $ foldl (\e name -> Map.insert (T.unpack name) t e) env namesList
+        Nothing -> return env
+
+termVersions :: Connection -> String -> IO [(Text, T, Integer)]
+termVersions conn name = do
+  let nameText = T.pack name
+  results <- query conn
+    ("SELECT hash, created_at FROM terms WHERE (names = ? OR names LIKE ? OR names LIKE ? OR names LIKE ?) ORDER BY created_at DESC")
+    (nameText, nameText <> T.pack ",%", T.pack "%," <> nameText <> T.pack ",%", T.pack "%," <> nameText)
+
+  catMaybes <$> mapM (\(hashVal, timestamp) -> do
+    maybeT <- loadTree conn hashVal
+    return $ fmap (\t -> (hashVal, t, timestamp)) maybeT
+    ) results
+
+setTag :: Connection -> Text -> Text -> IO ()
+setTag conn hash tagValue = do
+  exists <- termExists conn hash
+  if exists
+    then do
+      currentTagsQuery <- query conn "SELECT tags FROM terms WHERE hash = ?" (Only hash) :: IO [Only Text]
+      case currentTagsQuery of
+        [Only tagsText] -> do
+          let tagsList = parseNameList tagsText
+              newTagsList = tagValue : tagsList
+              newTags = serializeNameList newTagsList
+          execute conn "UPDATE terms SET tags = ? WHERE hash = ?" (newTags, hash)
+        _ -> putStrLn $ "Term with hash " ++ T.unpack hash ++ " not found (should not happen if exists is true)"
+    else
+      putStrLn $ "Term with hash " ++ T.unpack hash ++ " does not exist"
+
+termExists :: Connection -> Text -> IO Bool
+termExists conn hash = do
+  results <- query conn "SELECT 1 FROM terms WHERE hash = ? LIMIT 1" (Only hash) :: IO [[Int]]
+  return $ not (null results)
+
+termToTags :: Connection -> Text -> IO [Text]
+termToTags conn hash = do
+  tagsQuery <- query conn "SELECT tags FROM terms WHERE hash = ?" (Only hash) :: IO [Only Text]
+  case tagsQuery of
+    [Only tagsText] -> return $ parseNameList tagsText
+    _ -> return []
+
+tagToTerm :: Connection -> Text -> IO [StoredTerm]
+tagToTerm conn tagValue = do
+  let pattern = "%" <> tagValue <> "%"
+  query conn (selectStoredTermFields <> " WHERE tags LIKE ? ORDER BY created_at DESC") (Only pattern)
+
+allTermTags :: Connection -> IO [StoredTerm]
+allTermTags conn = do
+  query_ conn (selectStoredTermFields <> " WHERE tags IS NOT NULL AND tags != '' ORDER BY created_at DESC")
+
+selectStoredTermFields :: Query
+selectStoredTermFields = "SELECT hash, names, metadata, created_at, tags FROM terms"
+
+queryMaybeOne :: (FromRow r, ToRow q) => Connection -> Query -> q -> IO (Maybe r)
+queryMaybeOne conn qry params = do
+  results <- query conn qry params
+  case results of
+    [row] -> return $ Just row
+    _     -> return Nothing
+
+-- | Resolve a user-supplied identifier (full/prefix hash, term name) to
+--   a single term hash and the list of names bound to it.  Dies on
+--   ambiguity or missing term (matching the CLI @export@ semantics).
+resolveExportTarget :: Connection -> String -> IO (Text, [Text])
+resolveExportTarget conn input = do
+  let raw = T.pack $ dropWhile (== '#') input
+  byName <- query conn
+    "SELECT hash FROM terms WHERE (names = ? OR names LIKE ? OR names LIKE ? OR names LIKE ?) ORDER BY created_at DESC"
+    (raw, raw <> T.pack ",%", T.pack "," <> raw <> T.pack ",%", T.pack "%," <> raw) :: IO [Only T.Text]
+  case byName of
+    [Only fullHash] -> namesForHash conn fullHash >>= \names -> return (fullHash, names)
+    (_:_) -> die $ "Ambiguous term name: " ++ input
+    [] -> do
+      byHash <- query conn "SELECT hash FROM terms WHERE hash LIKE ? ORDER BY created_at DESC"
+        (Only (raw <> T.pack "%")) :: IO [Only T.Text]
+      case byHash of
+        [Only fullHash] -> namesForHash conn fullHash >>= \names -> return (fullHash, names)
+        [] -> if looksLikeHash raw
+          then return (raw, [])
+          else die $ "No term found matching: " ++ input
+        _ -> die $ "Ambiguous hash prefix: " ++ input
+
+namesForHash :: Connection -> Text -> IO [Text]
+namesForHash conn h = do
+  stored <- hashToTerm conn h
+  return $ maybe [] (parseNameList . termNames) stored
+
+-- | Return 'True' when @t@ looks like a full or partial SHA-256 hex hash.
+looksLikeHash :: Text -> Bool
+looksLikeHash t =
+  let len = T.length t
+  in len >= 16 && len <= 64 && T.all isHexDigit t

src/Eval.hs

@@ -1,120 +1,232 @@
 module Eval where
 
+import ContentStore
 import Parser
 import Research
 
-import Data.List (partition, (\\))
-import Data.Map  (Map)
+import Control.Monad (foldM)
+import Data.List (partition, (\\), elemIndex, foldl')
+import Data.Map  ()
+import Data.Set  (Set)
+import Database.SQLite.Simple
+
+import qualified Data.Foldable as F ()
 import qualified Data.Map as Map
 import qualified Data.Set as Set
+import qualified Data.Text as T
+
+data DB
+  = BVar Int
+  | BFree String
+  | BLam DB
+  | BApp DB DB
+  | BLeaf
+  | BStem DB
+  | BFork DB DB
+  | BStr String
+  | BInt Integer
+  | BList [DB]
+  | BEmpty
+  deriving (Eq, Show)
+
+type Uses = [Bool]
 
 evalSingle :: Env -> TricuAST -> Env
 evalSingle env term
   | SDef name [] body <- term
   = case Map.lookup name env of
       Just existingValue
-        | existingValue == evalAST env body -> env
-        | otherwise -> errorWithoutStackTrace $
-            "Unable to rebind immutable identifier: " ++ name
-      Nothing ->
-        let res = evalAST env body
-        in Map.insert "!result" res (Map.insert name res env)
+        | existingValue == evalASTSync env body -> env
+        | otherwise
+        -> let res = evalASTSync env body
+           in Map.insert "!result" res (Map.insert name res env)
+      Nothing
+        -> let res = evalASTSync env body
+           in Map.insert "!result" res (Map.insert name res env)
   | SApp func arg <- term
-  = let res = apply (evalAST env func) (evalAST env arg)
-      in Map.insert "!result" res env
-  | SVar name <- term
+  = let res = apply (evalASTSync env func) (evalASTSync env arg)
+    in Map.insert "!result" res env
+  | SVar name Nothing <- term
   = case Map.lookup name env of
-        Just v  -> Map.insert "!result" v env
-        Nothing ->
-          errorWithoutStackTrace $ "Variable `" ++ name ++ "` not defined\n\
-          \This error should never occur here. Please report this as an issue."
+      Just v -> Map.insert "!result" v env
+      Nothing -> errorWithoutStackTrace $ "Variable " ++ name ++ " not defined"
+  | SVar name (Just hash) <- term
+  = errorWithoutStackTrace $ "Hash-specific variable lookup not supported in local evaluation: " ++ name ++ "#" ++ hash
   | otherwise
-  = Map.insert "!result" (evalAST env term) env
+  = let res = evalASTSync env term
+    in Map.insert "!result" res env
 
 evalTricu :: Env -> [TricuAST] -> Env
 evalTricu env x = go env (reorderDefs env x)
   where
-    go env []     = env
-    go env [x]    =
-      let updatedEnv = evalSingle env x
+    go env' []     = env'
+    go env' [def]    =
+      let updatedEnv = evalSingle env' def
       in Map.insert "!result" (result updatedEnv) updatedEnv
-    go env (x:xs) =
-      evalTricu (evalSingle env x) xs
+    go env' (def:xs) =
+      evalTricu (evalSingle env' def) xs
 
-evalAST :: Env -> TricuAST -> T
-evalAST env term
-  | SLambda _ _ <- term = evalAST env (elimLambda term)
-  | SVar   name <- term = evalVar name
-  | TLeaf       <- term = Leaf
-  | TStem  t    <- term = Stem (evalAST env t)
-  | TFork  t u  <- term = Fork (evalAST env t) (evalAST env u)
-  | SApp   t u  <- term = apply (evalAST env t) (evalAST env u)
-  | SStr   s    <- term = ofString s
-  | SInt   n    <- term = ofNumber n
-  | SList  xs   <- term = ofList (map (evalAST env) xs)
-  | SEmpty      <- term = Leaf
-  | otherwise           = errorWithoutStackTrace "Unexpected AST term"
-    where
-      evalVar name = Map.findWithDefault
-        (errorWithoutStackTrace $ "Variable " ++ name ++ " not defined")
-        name env
+evalASTSync :: Env -> TricuAST -> T
+evalASTSync env term = case term of
+  SLambda _ _ -> evalASTSync env (elimLambda term)
+  SVar name Nothing -> case Map.lookup name env of
+    Just v -> v
+    Nothing -> errorWithoutStackTrace $ "Variable " ++ name ++ " not defined"
+  SVar name (Just hash) ->
+    case Map.lookup (name ++ "#" ++ hash) env of
+      Just v -> v
+      Nothing -> errorWithoutStackTrace $
+        "Variable " ++ name ++ " with hash " ++ hash ++ " not found in environment"
+  TLeaf -> Leaf
+  TStem t -> Stem (evalASTSync env t)
+  TFork t u -> Fork (evalASTSync env t) (evalASTSync env u)
+  SApp t u -> apply (evalASTSync env t) (evalASTSync env u)
+  SStr s -> ofString s
+  SInt n -> ofNumber n
+  SList xs -> ofList (map (evalASTSync env) xs)
+  SEmpty -> Leaf
+  _ -> errorWithoutStackTrace $ "Unexpected AST term: " ++ show term
+
+evalAST :: Maybe Connection -> Map.Map String T.Text -> TricuAST -> IO T
+evalAST mconn selectedVersions ast = do
+  let varNames = collectVarNames ast
+  resolvedEnv <- resolveTermsFromStore mconn selectedVersions varNames
+  return $ evalASTSync resolvedEnv ast
+
+collectVarNames :: TricuAST -> [(String, Maybe String)]
+collectVarNames = go []
+  where
+    go acc (SVar name mhash) = (name, mhash) : acc
+    go acc (SApp t u) = go (go acc t) u
+    go acc (SLambda vars body) =
+      let boundVars = Set.fromList vars
+          collected = go [] body
+      in acc ++ filter (\(name, _) -> not $ Set.member name boundVars) collected
+    go acc (TStem t) = go acc t
+    go acc (TFork t u) = go (go acc t) u
+    go acc (SList xs) = foldl' go acc xs
+    go acc _ = acc
+
+resolveTermsFromStore :: Maybe Connection -> Map.Map String T.Text -> [(String, Maybe String)] -> IO Env
+resolveTermsFromStore Nothing _ _ = return Map.empty
+resolveTermsFromStore (Just conn) selectedVersions varNames = do
+  foldM (\env (name, mhash) -> do
+    term <- resolveTermFromStore conn selectedVersions name mhash
+    case term of
+      Just t -> return $ Map.insert (getVarKey name mhash) t env
+      Nothing -> return env
+      ) Map.empty varNames
+  where
+    getVarKey name Nothing = name
+    getVarKey name (Just hash) = name ++ "#" ++ hash
+
+resolveTermFromStore :: Connection -> Map.Map String T.Text -> String -> Maybe String -> IO (Maybe T)
+resolveTermFromStore conn selectedVersions name mhash = case mhash of
+  Just hashPrefix -> do
+    versions <- termVersions conn name
+    let matchingVersions = filter (\(hash, _, _) ->
+          T.isPrefixOf (T.pack hashPrefix) hash) versions
+    case matchingVersions of
+      [] -> return Nothing
+      [(_, term, _)] -> return $ Just term
+      _ -> return Nothing
+  Nothing -> case Map.lookup name selectedVersions of
+    Just hash -> loadTree conn hash
+    Nothing -> do
+      versions <- termVersions conn name
+      case versions of
+        [] -> return Nothing
+        [(_, term, _)] -> return $ Just term
+        _ -> return $ Just (head (map (\(_, t, _) -> t) versions))
 
 elimLambda :: TricuAST -> TricuAST
 elimLambda = go
   where
-    -- η-reduction
-    go (SLambda [v] (SApp f (SVar x)))
-      | v == x && not (isFree v f) = elimLambda f
-    -- Triage optimization
-    go (SLambda [a] (SLambda [b] (SLambda [c] body)))
-      | body == triageBody         = _TRIAGE
+    go term
+      | etaReduction term   = go (etaReduceResult term)
+      | triagePattern term  = _TRI
+      | composePattern term = _B
+      | lambdaList term     = go (lambdaListResult term)
+      | nestedLambda term   = nestedLambdaResult term
+      | application term    = applicationResult term
+      | isSList term        = slistTransform term
+      | otherwise           = term
+
+    etaReduction (SLambda [v] (SApp f (SVar x Nothing))) = v == x && not (usesBinder v f)
+    etaReduction _ = False
+
+    triagePattern (SLambda [a] (SLambda [b] (SLambda [c] body))) =
+      toDB [c,b,a] body == triageBodyDB
+    triagePattern _ = False
+
+    composePattern (SLambda [f] (SLambda [g] (SLambda [x] body))) =
+      toDB [x,g,f] body == composeBodyDB
+    composePattern _ = False
+
+    lambdaList (SLambda [_] (SList _)) = True
+    lambdaList _ = False
+
+    nestedLambda (SLambda (_:_) _) = True
+    nestedLambda _ = False
+
+    application (SApp _ _) = True
+    application _ = False
+
+    etaReduceResult (SLambda [_] (SApp f _)) = f
+    etaReduceResult _ = error "etaReduceResult: expected SLambda [v] (SApp f _)"
+
+    lambdaListResult (SLambda [v] (SList xs)) =
+      SLambda [v] (foldr wrapTLeaf TLeaf xs)
       where
-        triageBody =
-          SApp (SApp TLeaf (SApp (SApp TLeaf (SVar a)) (SVar b))) (SVar c)
-    -- Composition optimization
-    go (SLambda [f] (SLambda [g] (SLambda [x] body)))
-      | body == SApp (SVar f) (SApp (SVar g) (SVar x)) = _B
-    -- General elimination
-    go (SLambda [v] (SList xs))
-      = elimLambda (SLambda [v] (foldr wrapTLeaf TLeaf xs))
-        where wrapTLeaf m r = SApp (SApp TLeaf m) r
-    go (SLambda (v:vs) body)
-      | null vs                    = toSKI v (elimLambda body)
-      | otherwise                  = elimLambda (SLambda [v] (SLambda vs body))
-    go (SApp f g)                  = SApp (elimLambda f) (elimLambda g)
-    go x                           = x
+        wrapTLeaf m r = SApp (SApp TLeaf m) r
+    lambdaListResult _ = error "lambdaListResult: expected SLambda [v] (SList xs)"
 
-    toSKI x (SVar y)
-      | x == y           = _I
-      | otherwise        = SApp _K (SVar y)
-    toSKI x t@(SApp n u)
-      | not (isFree x t) = SApp _K t
-      | otherwise        = SApp (SApp _S (toSKI x n)) (toSKI x u)
-    toSKI x t
-      | not (isFree x t) = SApp _K t
-      | otherwise        = errorWithoutStackTrace "Unhandled toSKI conversion"
+    nestedLambdaResult (SLambda (v:vs) body)
+      | null vs   =
+          let body' = go body
+              db    = toDB [v] body'
+          in toSKIKiselyov db
+      | otherwise = go (SLambda [v] (SLambda vs body))
+    nestedLambdaResult _ = error "nestedLambdaResult: expected SLambda (_:_) _"
 
-    _S       = parseSingle "t (t (t t t)) t"
-    _K       = parseSingle "t t"
-    _I       = parseSingle "t (t (t t)) t"
-    _B       = parseSingle "t (t (t t (t (t (t t t)) t))) (t t)"
-    _TRIAGE  = parseSingle "t (t (t t (t (t (t t t))))) t"
+    applicationResult (SApp f g) = SApp (go f) (go g)
+    applicationResult _ = error "applicationResult: expected SApp _ _"
+
+    isSList (SList _) = True
+    isSList _         = False
+
+    slistTransform :: TricuAST -> TricuAST
+    slistTransform (SList xs) = foldr (\m r -> SApp (SApp TLeaf (go m)) r) TLeaf xs
+    slistTransform ast = ast -- Should not be reached
+
+_S, _K, _I, _R, _C, _B, _T, _TRI :: TricuAST
+_S   = parseSingle "t (t (t t t)) t"
+_K   = parseSingle "t t"
+_I   = parseSingle "t (t (t t)) t"
+_R   = parseSingle "(t (t (t t (t (t (t (t (t (t (t t (t (t (t t t)) t))) (t (t (t t (t t))) (t (t (t t t)) t)))) (t t (t t))))))) (t t))"
+_C   = parseSingle "(t (t (t (t (t t (t (t (t t t)) t))) (t (t (t t (t t))) (t (t (t t t)) t)))) (t t (t t)))"
+_B   = parseSingle "t (t (t t (t (t (t t t)) t))) (t t)"
+_T   = SApp _C _I
+_TRI = parseSingle "t (t (t t (t (t (t t t))))) t"
+
+triageBody  :: String -> String -> String -> TricuAST
+triageBody a b c   = SApp (SApp TLeaf (SApp (SApp TLeaf (SVar a Nothing)) (SVar b Nothing))) (SVar c Nothing)
+composeBody :: String -> String -> String -> TricuAST
+composeBody f g x  = SApp (SVar f Nothing) (SApp (SVar g Nothing) (SVar x Nothing))
 
 isFree :: String -> TricuAST -> Bool
-isFree x = Set.member x . freeVars
+isFree x t = Set.member x (freeVars t)
 
-freeVars :: TricuAST -> Set.Set String
-freeVars (SVar    v    ) = Set.singleton v
-freeVars (SInt    _    ) = Set.empty
-freeVars (SStr    _    ) = Set.empty
-freeVars (SList   s    ) = foldMap freeVars s
-freeVars (SApp    f a  ) = freeVars f <> freeVars a
-freeVars  TLeaf          = Set.empty
-freeVars (SDef   _ _ b)  = freeVars b
-freeVars (TStem   t    ) = freeVars t
-freeVars (TFork   l r  ) = freeVars l <> freeVars r
-freeVars (SLambda v b  ) = foldr Set.delete (freeVars b) v
-freeVars  _              = Set.empty
+-- Keep old freeVars for compatibility with reorderDefs which still uses TricuAST
+freeVars :: TricuAST -> Set String
+freeVars (SVar v Nothing) = Set.singleton v
+freeVars (SVar v (Just _)) = Set.singleton v
+freeVars (SApp t u) = Set.union (freeVars t) (freeVars u)
+freeVars (SLambda vs body) = Set.difference (freeVars body) (Set.fromList vs)
+freeVars (TStem t) = freeVars t
+freeVars (TFork t u) = Set.union (freeVars t) (freeVars u)
+freeVars (SList xs) = foldMap freeVars xs
+freeVars _ = Set.empty
 
 reorderDefs :: Env -> [TricuAST] -> [TricuAST]
 reorderDefs env defs
@@ -131,7 +243,7 @@ reorderDefs env defs
     graph = buildDepGraph defsOnly
     sortedDefs = sortDeps graph
     defMap = Map.fromList [(name, def) | def@(SDef name _ _) <- defsOnly]
-    orderedDefs = map (\name -> defMap Map.! name) sortedDefs
+    orderedDefs = map (defMap Map.!) sortedDefs
 
     freeVarsDefs = foldMap snd defsWithFreeVars
     freeVarsOthers = foldMap freeVars others
@@ -139,8 +251,8 @@ reorderDefs env defs
     validNames = Set.fromList defNames `Set.union` Set.fromList (Map.keys env)
     missingDeps = Set.toList (allFreeVars `Set.difference` validNames)
 
-    isDef (SDef _ _ _) = True
-    isDef _            = False
+    isDef SDef {} = True
+    isDef _       = False
 
 buildDepGraph :: [TricuAST] -> Map.Map String (Set.Set String)
 buildDepGraph topDefs
@@ -165,7 +277,7 @@ buildDepGraph topDefs
 sortDeps :: Map.Map String (Set.Set String) -> [String]
 sortDeps graph = go [] Set.empty (Map.keys graph)
   where
-    go sorted sortedSet [] = sorted
+    go sorted _sortedSet [] = sorted
     go sorted sortedSet remaining =
       let ready = [ name | name <- remaining
                         , let deps = Map.findWithDefault Set.empty name graph
@@ -195,3 +307,289 @@ mainResult :: Env -> T
 mainResult r = case Map.lookup "main" r of
   Just  a -> a
   Nothing -> errorWithoutStackTrace "No valid definition for `main` found."
+
+findVarNames :: TricuAST -> [String]
+findVarNames ast = case ast of
+  SVar name _ -> [name]
+  SApp a b -> findVarNames a ++ findVarNames b
+  SLambda args body -> findVarNames body \\ args
+  SDef name args body -> name : (findVarNames body \\ args)
+  _ -> []
+
+-- Convert named TricuAST to De Bruijn form
+toDB :: [String] -> TricuAST -> DB
+toDB env = \case
+  SVar v _     -> maybe (BFree v) BVar (elemIndex v env)
+  SLambda vs b ->
+    let env' = reverse vs ++ env
+        body = toDB env' b
+    in foldr (\_ acc -> BLam acc) body vs
+  SApp f a     -> BApp (toDB env f) (toDB env a)
+  TLeaf        -> BLeaf
+  TStem t      -> BStem (toDB env t)
+  TFork l r    -> BFork (toDB env l) (toDB env r)
+  SStr s       -> BStr s
+  SInt n       -> BInt n
+  SList xs     -> BList (map (toDB env) xs)
+  SEmpty       -> BEmpty
+  SDef{}       -> error "toDB: unexpected SDef at this stage"
+  SImport _ _  -> BEmpty
+
+-- Does a term depend on the current binder (level 0)?
+dependsOnLevel :: Int -> DB -> Bool
+dependsOnLevel lvl = \case
+  BVar k      -> k == lvl
+  BLam t      -> dependsOnLevel (lvl + 1) t
+  BApp f a    -> dependsOnLevel lvl f || dependsOnLevel lvl a
+  BStem t     -> dependsOnLevel lvl t
+  BFork l r   -> dependsOnLevel lvl l || dependsOnLevel lvl r
+  BList xs    -> any (dependsOnLevel lvl) xs
+  _           -> False
+
+-- Collect free *global* names (i.e., unbound)
+freeDBNames :: DB -> Set String
+freeDBNames = \case
+  BFree s   -> Set.singleton s
+  BVar _    -> mempty
+  BLam t    -> freeDBNames t
+  BApp f a  -> freeDBNames f <> freeDBNames a
+  BLeaf     -> mempty
+  BStem t   -> freeDBNames t
+  BFork l r -> freeDBNames l <> freeDBNames r
+  BStr _    -> mempty
+  BInt _    -> mempty
+  BList xs  -> foldMap freeDBNames xs
+  BEmpty    -> mempty
+
+-- Helper: "is the binder named v used in body?"
+usesBinder :: String -> TricuAST -> Bool
+usesBinder v body = dependsOnLevel 0 (toDB [v] body)
+
+-- Expected DB bodies for the named special patterns (under env [a,b,c] -> indices 2,1,0)
+triageBodyDB :: DB
+triageBodyDB =
+  BApp (BApp BLeaf (BApp (BApp BLeaf (BVar 2)) (BVar 1))) (BVar 0)
+
+composeBodyDB :: DB
+composeBodyDB =
+  BApp (BVar 2) (BApp (BVar 1) (BVar 0))
+
+-- Convert DB -> TricuAST for subterms that contain NO binders (no BLam, no BVar)
+fromDBClosed :: DB -> TricuAST
+fromDBClosed = \case
+  BFree s   -> SVar s Nothing
+  BApp f a  -> SApp (fromDBClosed f) (fromDBClosed a)
+  BLeaf     -> TLeaf
+  BStem t   -> TStem (fromDBClosed t)
+  BFork l r -> TFork (fromDBClosed l) (fromDBClosed r)
+  BStr s    -> SStr s
+  BInt n    -> SInt n
+  BList xs  -> SList (map fromDBClosed xs)
+  BEmpty    -> SEmpty
+  -- Anything bound would be a logic error if we call this correctly.
+  BLam _    -> error "fromDBClosed: unexpected BLam"
+  BVar _    -> error "fromDBClosed: unexpected bound variable"
+
+-- DB-native bracket abstraction over the innermost binder (level 0).
+-- This mirrors your old toSKI, but is purely index-driven.
+toSKIDB :: DB -> TricuAST
+toSKIDB t
+  | not (dependsOnLevel 0 t) = SApp _K (fromDBClosed t)
+toSKIDB (BVar 0)             = _I
+toSKIDB (BApp n u)           = SApp (SApp _S (toSKIDB n)) (toSKIDB u)
+toSKIDB (BStem t)             = toSKIDB (BApp BLeaf t)
+toSKIDB (BFork l r)           = toSKIDB (BApp (BApp BLeaf l) r)
+toSKIDB (BList xs)            = toSKIDB (foldr (\m r -> BApp (BApp BLeaf m) r) BLeaf xs)
+toSKIDB other                 = error $ "toSKIDB: unsupported DB term: " ++ show other
+
+app2 :: TricuAST -> TricuAST -> TricuAST
+app2 f x = SApp f x
+
+app3 :: TricuAST -> TricuAST -> TricuAST -> TricuAST
+app3 f x y = SApp (SApp f x) y
+
+-- Core converter that *does not* perform the λ-step; it just returns (Γ, d).
+-- Supported shapes: variables, applications, closed literals (Leaf/Int/Str/Empty),
+-- closed lists. For anything where the binder occurs under structural nodes
+-- (Stem/Fork/List-with-use), we deliberately bail so the caller can fall back.
+kisConv :: DB -> Either String (Uses, TricuAST)
+kisConv = \case
+  BVar 0     -> Right ([True], _I)
+  BVar n | n > 0 -> do
+    (g,d) <- kisConv (BVar (n - 1))
+    Right (False:g, d)
+  BVar n     -> Right ([], SVar ("BVar" ++ show n) Nothing)
+  BFree s    -> Right ([], SVar s Nothing)
+  BApp e1 e2 -> do
+    (g1,d1) <- kisConv e1
+    (g2,d2) <- kisConv e2
+    let g = zipWithDefault False (||) g1 g2   -- <- propagate Γ outside (#)
+        d = kisHash (g1,d1) (g2,d2)           -- <- (#) yields only the term
+    Right (g, d)
+  -- Treat closed constants as free 'combinator leaves' (no binder use).
+  BLeaf      -> Right ([], TLeaf)
+  BStr s     -> Right ([], SStr s)
+  BInt n     -> Right ([], SInt n)
+  BEmpty     -> Right ([], SEmpty)
+  -- Closed list: allowed. If binder is used anywhere, we punt to fallback.
+  BList xs
+    | any (dependsOnLevel 0) xs -> Left "List with binder use: fallback"
+    | otherwise                 -> Right ([], SList (map fromDBClosed xs))
+  -- For structural nodes, only allow if *closed* wrt the binder.
+  BStem t
+    | dependsOnLevel 0 t -> Left "Stem with binder use: fallback"
+    | otherwise          -> Right ([], TStem (fromDBClosed t))
+  BFork l r
+    | dependsOnLevel 0 l || dependsOnLevel 0 r -> Left "Fork with binder use: fallback"
+    | otherwise                                -> Right ([], TFork (fromDBClosed l) (fromDBClosed r))
+  -- We shouldn't see BLam under elim; treat as unsupported so we fallback.
+  BLam _      -> Left "Nested lambda under body: fallback"
+
+-- Application combiner with K-optimization (lazy weakening).
+-- Mirrors Lynn's 'optK' rules: choose among S, B, C, R based on leading flags.
+-- η-aware (#) with K-optimization (adapted from TS kiselyov_eta)
+kisHash :: (Uses, TricuAST) -> (Uses, TricuAST) -> TricuAST
+kisHash (g1, d1) (g2, d2) =
+  case g1 of
+    [] -> case g2 of
+      []            -> SApp d1 d2
+      True:gs2      -> if isId2 (g2, d2)
+                         then d1
+                         else kisHash ([], SApp _B d1) (gs2, d2)
+      False:gs2     -> kisHash ([], d1) (gs2, d2)
+
+    True:gs1 -> case g2 of
+      []            -> if isId2 (g1, d1)
+                         then SApp _T d2
+                         else kisHash ([], SApp _R d2) (gs1, d1)
+      _ ->
+        if isId2 (g1, d1) && case g2 of { False:_ -> True; _ -> False }
+          then kisHash ([], _T) (drop1 g2, d2)
+        else
+          -- NEW: coalesce the longest run of identical head pairs and apply bulk op once
+          let ((h1, h2), count) = headPairRun g1 g2
+              g1' = drop count g1
+              g2' = drop count g2
+          in case (h1, h2) of
+               (False, False) ->
+                 kisHash (g1', d1) (g2', d2)
+               (False, True)  ->
+                 let d1' = kisHash ([], bulkB count) (g1', d1)
+                 in  kisHash (g1', d1') (g2', d2)
+               (True, False)  ->
+                 let d1' = kisHash ([], bulkC count) (g1', d1)
+                 in  kisHash (g1', d1') (g2', d2)
+               (True, True)   ->
+                 let d1' = kisHash ([], bulkS count) (g1', d1)
+                 in  kisHash (g1', d1') (g2', d2)
+
+    False:gs1 -> case g2 of
+      []            -> kisHash (gs1, d1) ([], d2)
+      _             ->
+        if isId2 (g1, d1) && case g2 of { False:_ -> True; _ -> False }
+          then kisHash ([], _T) (drop1 g2, d2)
+        else case g2 of
+          True:gs2   ->
+            let d1' = kisHash ([], _B) (gs1, d1)
+            in  kisHash (gs1, d1') (gs2, d2)
+          False:gs2  ->
+            kisHash (gs1, d1) (gs2, d2)
+  where
+    drop1 (_:xs) = xs
+    drop1 []     = []
+
+
+toSKIKiselyov :: DB -> TricuAST
+toSKIKiselyov body =
+  case kisConv body of
+    Right ([], d)          -> SApp _K d
+    Right (True:_ , d)     -> d
+    Right (False:g, d)     -> kisHash ([], _K) (g, d)  -- no snd
+    Left _                 -> starSKIBCOpEtaDB body   -- was: toSKIDB body
+
+zipWithDefault :: a -> (a -> a -> a) -> [a] -> [a] -> [a]
+zipWithDefault d f []     ys     = map (f d) ys
+zipWithDefault d f xs     []     = map (\x -> f x d) xs
+zipWithDefault d f (x:xs) (y:ys) = f x y : zipWithDefault d f xs ys
+
+isNode :: TricuAST -> Bool
+isNode t = case t of
+  TLeaf -> True
+  _     -> False
+
+isApp2 :: TricuAST -> Maybe (TricuAST, TricuAST)
+isApp2 (SApp a b) = Just (a, b)
+isApp2 _          = Nothing
+
+isKop :: TricuAST -> Bool
+isKop t = case isApp2 t of
+  Just (a,b) -> isNode a && isNode b
+  _          -> False
+
+-- detects the two canonical I-shapes in the tree calculus:
+--   △ (△ (△ △)) x    OR    △ (△ △ △) △
+isId :: TricuAST -> Bool
+isId t = case isApp2 t of
+  Just (ab, c) -> case isApp2 ab of
+    Just (a, b) | isNode a ->
+      case isApp2 b of
+        Just (b1, b2) ->
+          (isNode b1 && isKop b2) ||
+          (isKop b1 && isNode b2 && isNode c)
+        _ -> False
+    _ -> False
+  _ -> False
+
+-- head-True only, tail empty, and term is identity
+isId2 :: (Uses, TricuAST) -> Bool
+isId2 (True:[], t) = isId t
+isId2 _            = False
+
+-- Bulk helpers built from SKI (no new primitives)
+bPrime :: TricuAST
+bPrime = SApp _B _B                            -- B' = B B
+
+cPrime :: TricuAST
+cPrime = SApp (SApp _B (SApp _B _C)) _B        -- C' = B (B C) B
+
+sPrime :: TricuAST
+sPrime = SApp (SApp _B (SApp _B _S)) _B        -- S' = B (B S) B
+
+bulkB :: Int -> TricuAST
+bulkB n | n <= 1    = _B
+        | otherwise = SApp bPrime (bulkB (n - 1))
+
+bulkC :: Int -> TricuAST
+bulkC n | n <= 1    = _C
+        | otherwise = SApp cPrime (bulkC (n - 1))
+
+bulkS :: Int -> TricuAST
+bulkS n | n <= 1    = _S
+        | otherwise = SApp sPrime (bulkS (n - 1))
+
+headPairRun :: [Bool] -> [Bool] -> ((Bool, Bool), Int)
+headPairRun g1 g2 =
+  case zip g1 g2 of
+    []       -> ((False, False), 0)
+    (h:rest) -> (h, 1 + length (takeWhile (== h) rest))
+
+-- DB-native star_skibc_op_eta (adapted from strategies.mts), binder = level 0
+starSKIBCOpEtaDB :: DB -> TricuAST
+starSKIBCOpEtaDB t
+  | not (dependsOnLevel 0 t) = SApp _K (fromDBClosed t)
+starSKIBCOpEtaDB (BVar 0)     = _I
+starSKIBCOpEtaDB (BApp e1 e2)
+  -- if binder not in right: use C
+  | not (dependsOnLevel 0 e2)
+  = SApp (SApp _C (starSKIBCOpEtaDB e1)) (fromDBClosed e2)
+  -- if binder not in left:
+  | not (dependsOnLevel 0 e1)
+  = case e2 of
+      -- η case: \x. f x  ==>  f
+      BVar 0 -> fromDBClosed e1
+      _      -> SApp (SApp _B (fromDBClosed e1)) (starSKIBCOpEtaDB e2)
+  -- otherwise: S
+  | otherwise
+  = SApp (SApp _S (starSKIBCOpEtaDB e1)) (starSKIBCOpEtaDB e2)
+-- Structural nodes with binder underneath: fall back to plain SKI (rare)
+starSKIBCOpEtaDB other        = toSKIDB other

src/FileEval.hs

@@ -1,28 +1,40 @@
-module FileEval where
+module FileEval
+  ( preprocessFile
+  , evaluateFile
+  , evaluateFileWithContext
+  , evaluateFileResult
+  , compileFile
+  ) where
 
-import Eval
+import Eval (evalTricu)
 import Lexer
 import Parser
 import Research
+import ContentStore (initContentStore, storeTerm, hashTerm)
+import Wire (exportNamedBundle, defaultExportNames)
 
+import Control.Monad   (forM_)
 import Data.List       (partition)
 import Data.Maybe      (mapMaybe)
-import Control.Monad   (foldM)
-import System.IO
+import System.Environment (setEnv)
 import System.FilePath (takeDirectory, normalise, (</>))
+import System.Exit (die)
+import Database.SQLite.Simple (close)
 
+import qualified Data.ByteString.Lazy as BL
 import qualified Data.Map as Map
 import qualified Data.Set as Set
+import qualified Data.Text as T
 
 extractMain :: Env -> Either String T
 extractMain env =
   case Map.lookup "main" env of
-    Just result -> Right result
+    Just evalResult -> Right evalResult
     Nothing -> Left "No `main` function detected"
 
 processImports :: Set.Set FilePath -> FilePath -> FilePath -> [TricuAST]
                  -> Either String ([TricuAST], [(FilePath, String, FilePath)])
-processImports seen base currentPath asts =
+processImports seen _base currentPath asts =
   let (imports, nonImports) = partition isImp asts
       importPaths = mapMaybe getImportInfo imports
   in if currentPath `Set.member` seen
@@ -40,11 +52,11 @@ evaluateFileResult filePath = do
   let tokens = lexTricu contents
   case parseProgram tokens of
     Left err -> errorWithoutStackTrace (handleParseError err)
-    Right ast -> do
+    Right _ast -> do
       processedAst <- preprocessFile filePath
       let finalEnv = evalTricu Map.empty processedAst
       case extractMain finalEnv of
-        Right result -> return result
+        Right evalResult -> return evalResult
         Left err -> errorWithoutStackTrace err
 
 evaluateFile :: FilePath -> IO Env
@@ -53,7 +65,7 @@ evaluateFile filePath = do
   let tokens = lexTricu contents
   case parseProgram tokens of
     Left err -> errorWithoutStackTrace (handleParseError err)
-    Right ast -> do
+    Right _ast -> do
       ast <- preprocessFile filePath
       pure $ evalTricu Map.empty ast
 
@@ -63,7 +75,7 @@ evaluateFileWithContext env filePath = do
   let tokens = lexTricu contents
   case parseProgram tokens of
     Left err -> errorWithoutStackTrace (handleParseError err)
-    Right ast -> do
+    Right _ast -> do
       ast <- preprocessFile filePath
       pure $ evalTricu env ast
 
@@ -84,8 +96,8 @@ preprocessFile' seen base currentPath = do
           imported <- concat <$> mapM (processImportPath seen' base) importPaths
           pure $ imported ++ nonImports
   where
-    processImportPath seen base (path, name, importPath) = do
-      ast <- preprocessFile' seen base importPath
+    processImportPath _seen _base (_path, name, importPath) = do
+      ast <- preprocessFile' _seen _base importPath
       pure $ map (nsDefinition (if name == "!Local" then "" else name))
            $ filter (not . isImp) ast
     isImp (SImport _ _) = True
@@ -96,9 +108,6 @@ makeRelativeTo f i =
     let d = takeDirectory f
     in normalise $ d </> i
 
-nsDefinitions :: String -> [TricuAST] -> [TricuAST]
-nsDefinitions moduleName = map (nsDefinition moduleName)
-
 nsDefinition :: String -> TricuAST -> TricuAST
 nsDefinition "" def = def
 nsDefinition moduleName (SDef name args body)
@@ -109,9 +118,9 @@ nsDefinition moduleName other =
   nsBody moduleName other
 
 nsBody :: String -> TricuAST -> TricuAST
-nsBody moduleName (SVar name)
-  | isPrefixed name = SVar name
-  | otherwise = SVar (nsVariable moduleName name)
+nsBody moduleName (SVar name mhash)
+  | isPrefixed name = SVar name mhash
+  | otherwise = SVar (nsVariable moduleName name) mhash
 nsBody moduleName (SApp func arg) =
   SApp (nsBody moduleName func) (nsBody moduleName arg)
 nsBody moduleName (SLambda args body) =
@@ -122,18 +131,16 @@ nsBody moduleName (TFork left right) =
   TFork (nsBody moduleName left) (nsBody moduleName right)
 nsBody moduleName (TStem subtree) =
   TStem (nsBody moduleName subtree)
-nsBody moduleName (SDef name args body)
-  | isPrefixed name = SDef name args (nsBody moduleName body)
-  | otherwise = SDef (nsVariable moduleName name)
-                        args (nsBody moduleName body)
+nsBody moduleName (SDef name args body) =
+  SDef (nsVariable moduleName name) args (nsBodyScoped moduleName args body)
 nsBody _ other = other
 
 nsBodyScoped :: String -> [String] -> TricuAST -> TricuAST
 nsBodyScoped moduleName args body = case body of
-  SVar name ->
+  SVar name mhash ->
     if name `elem` args
-      then SVar name
-      else nsBody moduleName (SVar name)
+      then SVar name mhash
+      else nsBody moduleName (SVar name mhash)
   SApp func arg ->
     SApp (nsBodyScoped moduleName args func) (nsBodyScoped moduleName args arg)
   SLambda innerArgs innerBody ->
@@ -141,13 +148,11 @@ nsBodyScoped moduleName args body = case body of
   SList items ->
     SList (map (nsBodyScoped moduleName args) items)
   TFork left right ->
-    TFork (nsBodyScoped moduleName args left)
-          (nsBodyScoped moduleName args right)
+    TFork (nsBodyScoped moduleName args left) (nsBodyScoped moduleName args right)
   TStem subtree ->
     TStem (nsBodyScoped moduleName args subtree)
   SDef name innerArgs innerBody ->
-    SDef (nsVariable moduleName name) innerArgs
-         (nsBodyScoped moduleName (args ++ innerArgs) innerBody)
+    SDef (nsVariable moduleName name) innerArgs (nsBodyScoped moduleName (args ++ innerArgs) innerBody)
   other -> other
 
 isPrefixed :: String -> Bool
@@ -156,3 +161,40 @@ isPrefixed name = '.' `elem` name
 nsVariable :: String -> String -> String
 nsVariable "" name = name
 nsVariable moduleName name = moduleName ++ "." ++ name
+
+-- | Compile a tricu source file to a standalone Arboricx bundle.
+-- Uses a temp content store so it does not collide with the global one.
+-- Supports multiple named exports; each is stored separately in the
+-- temp store so that resolveExportTarget can look them up by name.
+compileFile :: FilePath -> FilePath -> [T.Text] -> IO ()
+compileFile inputPath outputPath maybeNames = do
+  -- Evaluate the file to get the full environment
+  env <- evaluateFile inputPath
+  -- Look up each requested definition name
+  let defaultNames = ["main"]
+      wantedNames  = if null maybeNames then defaultNames else maybeNames
+      wantedNamesUnpacked = map T.unpack wantedNames
+  compiledTerms <- mapM (\n -> case Map.lookup n env of
+    Nothing -> die $ "No definition '" ++ n ++ "' found in " ++ inputPath
+    Just t  -> return (n, t)) wantedNamesUnpacked
+  let compiledMap :: Map.Map T.Text T = Map.fromList
+                $ map (\(n,t) -> (T.pack n, t)) compiledTerms
+      compiledNames :: [T.Text] = Map.keys compiledMap
+      compiledTermsList :: [T] = Map.elems compiledMap
+  -- Create a temp content store
+  setEnv "TRICU_DB_PATH" "/tmp/tricu-compile.db"
+  conn <- initContentStore
+  -- Store each term in the temp store under its requested name
+  forM_ (zip compiledNames compiledTermsList) $ \(n, t) ->
+    storeTerm conn [T.unpack n] t
+  -- Generate default export names when none were supplied
+  let expNames = if null maybeNames
+        then defaultExportNames (length compiledNames)
+        else compiledNames
+      exports :: [(T.Text, MerkleHash)] = zip expNames (map hashTerm compiledTermsList)
+  -- Export the bundle (exportNamedBundle returns already-encoded bytes)
+  bundleData <- exportNamedBundle conn exports
+  BL.writeFile outputPath (BL.fromStrict bundleData)
+  close conn
+  putStrLn $ "Compiled " ++ inputPath ++ " -> " ++ outputPath
+  putStrLn $ "  exports: " ++ T.unpack (T.intercalate ", " expNames)

src/Lexer.hs

@@ -3,13 +3,13 @@ module Lexer where
 import Research
 
 import Control.Monad               (void)
+import Data.Functor                (($>))
+import Data.Set ()
 import Data.Void
 import Text.Megaparsec
 import Text.Megaparsec.Char hiding (space)
 import Text.Megaparsec.Char.Lexer
 
-import qualified Data.Set as Set
-
 type Lexer = Parsec Void String
 
 tricuLexer :: Lexer [LToken]
@@ -22,25 +22,25 @@ tricuLexer = do
       ]
     sc
     pure tok
-  tokens <- many $ do
+  toks <- many $ do
     tok <- choice tricuLexer'
     sc
     pure tok
   sc
   eof
-  pure (header ++ tokens)
+  pure (header ++ toks)
   where
     tricuLexer' =
       [ try lnewline
       , try namespace
       , try dot
+      , try identifierWithHash
       , try identifier
       , try keywordT
       , try integerLiteral
       , try stringLiteral
       , assign
       , colon
-      , backslash
       , openParen
       , closeParen
       , openBracket
@@ -50,20 +50,43 @@ tricuLexer = do
 lexTricu :: String -> [LToken]
 lexTricu input = case runParser tricuLexer "" input of
   Left err -> errorWithoutStackTrace $ "Lexical error:\n" ++ errorBundlePretty err
-  Right tokens -> tokens
+  Right toks -> toks
 
 
 keywordT :: Lexer LToken
-keywordT = string "t" *> notFollowedBy alphaNumChar *> pure LKeywordT
+keywordT = string "t" *> notFollowedBy alphaNumChar $> LKeywordT
+
+identifierWithHash :: Lexer LToken
+identifierWithHash = do
+  first <- lowerChar <|> char '_'
+  rest  <- many $ letterChar
+              <|> digitChar <|> char '_' <|> char '-' <|> char '?'
+              <|> char '$'  <|> char '@' <|> char '%'
+                        <|> char '\''
+  _ <- char '#' -- Consume '#'
+  hashString <- some (alphaNumChar <|> char '-') -- Ensures at least one char for hash
+                <?> "hash characters (alphanumeric or hyphen)"
+
+  let name = first : rest
+  let hashLen = length hashString
+  if name == "t" || name == "!result"
+    then fail "Keywords (`t`, `!result`) cannot be used with a hash suffix."
+    else if hashLen < 16 then
+      fail $ "Hash suffix for '" ++ name ++ "' must be at least 16 characters long. Got " ++ show hashLen ++ " ('" ++ hashString ++ "')."
+    else if hashLen > 64 then -- Assuming SHA256, max 64
+      fail $ "Hash suffix for '" ++ name ++ "' cannot be longer than 64 characters (SHA256). Got " ++ show hashLen ++ " ('" ++ hashString ++ "')."
+    else
+      return (LIdentifierWithHash name hashString)
 
 identifier :: Lexer LToken
 identifier = do
   first <- lowerChar <|> char '_'
   rest  <- many $ letterChar
               <|> digitChar <|> char '_' <|> char '-' <|> char '?'
-              <|> char '$'  <|> char '#' <|> char '@' <|> char '%'
+              <|> char '$'  <|> char '@' <|> char '%'
+                        <|> char '\''
   let name = first : rest
-  if (name == "t" || name == "!result")
+  if name == "t" || name == "!result"
     then fail "Keywords (`t`, `!result`) cannot be used as an identifier"
     else return (LIdentifier name)
 
@@ -76,7 +99,7 @@ namespace = do
   return (LNamespace name)
 
 dot :: Lexer LToken
-dot = char '.' *> pure LDot
+dot = char '.' $> LDot
 
 lImport :: Lexer LToken
 lImport = do
@@ -88,28 +111,25 @@ lImport = do
   return (LImport path name)
 
 assign :: Lexer LToken
-assign = char '=' *> pure LAssign
+assign = char '=' $> LAssign
 
 colon :: Lexer LToken
-colon = char ':' *> pure LColon
-
-backslash :: Lexer LToken
-backslash = char '\\' *> pure LBackslash
+colon = char ':' $> LColon
 
 openParen :: Lexer LToken
-openParen = char '(' *> pure LOpenParen
+openParen = char '(' $> LOpenParen
 
 closeParen :: Lexer LToken
-closeParen = char ')' *> pure LCloseParen
+closeParen = char ')' $> LCloseParen
 
 openBracket :: Lexer LToken
-openBracket = char '[' *> pure LOpenBracket
+openBracket = char '[' $> LOpenBracket
 
 closeBracket :: Lexer LToken
-closeBracket = char ']' *> pure LCloseBracket
+closeBracket = char ']' $> LCloseBracket
 
 lnewline :: Lexer LToken
-lnewline = char '\n' *> pure LNewline
+lnewline = char '\n' $> LNewline
 
 sc :: Lexer ()
 sc = space
@@ -124,8 +144,24 @@ integerLiteral = do
 
 stringLiteral :: Lexer LToken
 stringLiteral = do
-  char '"'
-  content <- many (noneOf ['"'])
-  char '"' --"
+  void (char '"')
+  content <- manyTill Lexer.charLiteral (void (char '"'))
   return (LStringLiteral content)
 
+charLiteral :: Lexer Char
+charLiteral = escapedChar <|> normalChar
+  where
+    normalChar = noneOf ['"', '\\']
+    escapedChar = do
+      void $ char '\\'
+      c <- oneOf ['n', 't', 'r', 'f', 'b', '\\', '"', '\'']
+      return $ case c of
+        'n'  -> '\n'
+        't'  -> '\t'
+        'r'  -> '\r'
+        'f'  -> '\f'
+        'b'  -> '\b'
+        '\\' -> '\\'
+        '"'  -> '"'
+        '\'' -> '\''
+        _    -> c

src/Main.hs

@@ -1,24 +1,39 @@
 module Main where
 
+import ContentStore (initContentStore, loadEnvironment, loadTerm, resolveExportTarget)
+import System.Exit (die)
+import Server (runServer)
 import Eval                   (evalTricu, mainResult, result)
 import FileEval
 import Parser                 (parseTricu)
 import REPL
 import Research
+import Wire
 
 import Control.Monad          (foldM)
-import Control.Monad.IO.Class (liftIO)
+import Data.Text              (Text, unpack)
+import qualified Data.Text    as T
 import Data.Version           (showVersion)
-import Text.Megaparsec        (runParser)
 import Paths_tricu            (version)
 import System.Console.CmdArgs
+import System.Environment     (lookupEnv)
+import System.IO              (hPutStrLn, stderr)
+import Text.Megaparsec        ()
+
+import qualified Data.ByteString.Lazy as BL
+import Database.SQLite.Simple (close)
 
 import qualified Data.Map as Map
 
 data TricuArgs
   = Repl
-  | Evaluate { file :: [FilePath], form :: EvaluatedForm }
+  | Evaluate { file :: [FilePath], form :: EvaluatedForm, outFile :: FilePath }
   | TDecode { file :: [FilePath] }
+  | Compile { inputFile :: FilePath, outFile :: FilePath, names :: [String] }
+  | Export { hash :: String, exportNameOpt :: String, outFile :: FilePath, names :: [String] }
+  | Import { inFile :: FilePath }
+  | Serve { host :: String, port :: Int }
+  | ExportDag { target :: String, outFile :: FilePath }
   deriving (Show, Data, Typeable)
 
 replMode :: TricuArgs
@@ -36,6 +51,8 @@ evaluateMode = Evaluate
       &= help "Optional output form: (tree|fsl|ast|ternary|ascii|decode).\n \
       \ Defaults to tricu-compatible `t` tree form."
       &= name "t"
+    , outFile = def &= help "Optional output file path. Defaults to stdout."
+      &= name "o" &= typ "FILE"
   }
   &= help "Evaluate tricu and return the result of the final expression."
   &= explicit
@@ -52,38 +69,212 @@ decodeMode = TDecode
   &= explicit
   &= name "decode"
 
+exportMode :: TricuArgs
+exportMode = Export
+  { hash = def &= help "Hash or stored term name(s) to export (comma-separated)."
+             &= name "h" &= typ "HASH_OR_NAME"
+    , exportNameOpt = def &= help "Export name (legacy; use -n NAME for full control)."
+             &= name "n" &= typ "NAME"
+    , outFile = def &= help "Output file path for the bundle." &= name "o" &= typ "FILE"
+    , names = def &= help "Export name(s) for the bundle manifest (comma-separated or repeated -n)."
+               &= typ "NAME"
+  }
+  &= help "Export a Merkle bundle from the content store."
+  &= explicit
+  &= name "export"
+
+importMode :: TricuArgs
+importMode = Import
+  { inFile = def &= help "Path to the bundle file to import."
+               &= name "f" &= typ "FILE"
+  }
+  &= help "Import a Merkle bundle into the content store."
+  &= explicit
+  &= name "import"
+
+compileMode :: TricuArgs
+compileMode = Compile
+  { inputFile = def &= help "Path to the tricu source file (.tri) to compile."
+                  &= name "f" &= typ "FILE"
+  , outFile = def &= help "Output bundle file path (.tri.bundle)."
+                &= name "o" &= typ "FILE"
+  , names = def &= help "Definition name(s) to export as bundle roots (comma-separated or repeated -x). Defaults to 'main'."
+              &= name "x" &= typ "NAME"
+  }
+  &= help "Compile a tricu source file into a standalone Arboricx portable bundle."
+  &= explicit
+  &= name "compile"
+
+serveMode :: TricuArgs
+serveMode = Serve
+  { host = "127.0.0.1" &= help "Host to bind the server to." &= name "h" &= typ "HOST"
+    , port = 8787 &= help "HTTP port to listen on." &= name "p" &= typ "PORT"
+  }
+  &= help "Start a read-only HTTP server for exporting Arboricx bundles."
+  &= explicit
+  &= name "server"
+
+exportDagMode :: TricuArgs
+exportDagMode = ExportDag
+  { target = def &= help "Stored term name or hash to export as a DAG node table."
+                 &= name "t" &= typ "NAME_OR_HASH"
+  , outFile = def &= help "Optional output file path. Defaults to stdout."
+                  &= name "o" &= typ "FILE"
+  }
+  &= help "Export a term's Merkle DAG as a topologically-sorted node table for host embedding."
+  &= explicit
+  &= name "export-dag"
+
 main :: IO ()
 main = do
   let versionStr = "tricu Evaluator and REPL " ++ showVersion version
-  args <- cmdArgs $ modes [replMode, evaluateMode, decodeMode]
+  cmdArgsParsed <- cmdArgs $ modes [replMode, evaluateMode, decodeMode, compileMode, exportMode, importMode, serveMode, exportDagMode]
     &= help "tricu: Exploring Tree Calculus"
     &= program "tricu"
     &= summary versionStr
     &= versionArg [explicit, name "version", summary versionStr]
-  case args of
+  case cmdArgsParsed of
     Repl -> do
       putStrLn "Welcome to the tricu REPL"
-      putStrLn "You can exit with `CTRL+D` or the `!exit` command.`"
-      repl Map.empty
-    Evaluate { file = filePaths, form = form } -> do
-      result <- case filePaths of
+      putStrLn "You may exit with `CTRL+D` or the `!exit` command."
+      repl
+    Evaluate { file = filePaths, form = outputForm, outFile = evalOutFile } -> do
+      maybeDbPath <- lookupEnv "TRICU_DB_PATH"
+      evalResult <- case filePaths of
         [] -> do
-          t <- getContents
-          pure $ runTricu t
-        (filePath:restFilePaths) -> do
-            initialEnv <- evaluateFile filePath
-            finalEnv <- foldM evaluateFileWithContext initialEnv restFilePaths
+            initialEnv <- case maybeDbPath of
+              Just _ -> do
+                conn <- initContentStore
+                env <- loadEnvironment conn
+                close conn
+                return env
+              Nothing -> return Map.empty
+            input <- getContents
+            pure $ runTricuTEnv initialEnv input
+        filePaths@(_:_) -> do
+            initialEnv <- case maybeDbPath of
+              Just _ -> do
+                conn <- initContentStore
+                env <- loadEnvironment conn
+                close conn
+                return env
+              Nothing -> return Map.empty
+            finalEnv <- foldM evaluateFileWithContext initialEnv filePaths
             pure $ mainResult finalEnv
-      let fRes = formatResult form result
-      putStr fRes
+      let fRes = formatT outputForm evalResult
+      if null evalOutFile
+        then putStr fRes
+        else writeFile evalOutFile fRes
     TDecode { file = filePaths } -> do
       value <- case filePaths of
         [] -> getContents
         (filePath:_) -> readFile filePath
       putStrLn $ decodeResult $ result $ evalTricu Map.empty $ parseTricu value
+    Export { hash = hashStr, exportNameOpt = legacyName, names = namesArg, outFile = outFilePath } -> do
+      conn <- initContentStore
+      let hashList = T.split (== ',') (T.pack hashStr)
+      hashes <- mapM (\h -> do
+        (resolvedHash, _) <- resolveExportTarget conn (T.unpack h)
+        return resolvedHash) hashList
+      -- Merge legacy -n and new -n (names); names wins when non-empty
+      let allNames = if null namesArg
+            then if null legacyName then [] else [legacyName]
+            else namesArg
+      let expNames = if null allNames
+            then defaultExportNames (length hashes)
+            else map T.pack allNames
+      let exports = zip expNames hashes
+      bundleData <- exportNamedBundle conn exports
+      BL.writeFile outFilePath (BL.fromStrict bundleData)
+      putStrLn $ "Exported bundle with " ++ show (length exports) ++ " export(s) to " ++ outFilePath
+      close conn
+    Import { inFile = importFile } -> do
+      conn <- initContentStore
+      bundleData <- BL.readFile importFile
+      roots <- importBundle conn (BL.toStrict bundleData)
+      putStrLn $ "Imported " ++ show (length roots) ++ " root(s):"
+      mapM_ (\r -> putStrLn $ "  " ++ unpack r) roots
+      close conn
+    Compile { inputFile = compileInputFile, outFile = compileOutFile, names = namesArg } ->
+      let exportNames = if null namesArg then [] else map T.pack namesArg
+      in compileFile compileInputFile compileOutFile exportNames
+    Serve { host = hostStr, port = portNum } -> do
+      putStrLn $ "Starting Arboricx bundle server on " ++ hostStr ++ ":" ++ show portNum
+      putStrLn $ "  GET /bundle/hash/:hash   -- primary endpoint"
+      putStrLn $ "  GET /bundle/name/:name   -- convenience endpoint"
+      putStrLn $ "  Content-Type: application/vnd.arboricx.bundle"
+      runServer hostStr portNum
+    ExportDag { target = targetName, outFile = dagOutFile } -> do
+      conn <- initContentStore
+      maybeTerm <- loadTerm conn targetName
+      close conn
+      case maybeTerm of
+        Nothing -> die $ "Term not found: " ++ targetName
+        Just term -> do
+          let (rootIdx, nodes) = exportDag term
+              output = unlines $ show rootIdx : map (\(tag, refs) -> unwords (tag : map show refs)) nodes
+          if null dagOutFile
+            then putStr output
+            else writeFile dagOutFile output
 
-runTricu :: String -> T
-runTricu input =
+runTricu :: String -> String
+runTricu = formatT TreeCalculus . runTricuT
+
+runTricuT :: String -> T
+runTricuT input =
   let asts     = parseTricu input
       finalEnv = evalTricu Map.empty asts
    in result finalEnv
+
+runTricuEnv :: Env -> String -> String
+runTricuEnv env = formatT TreeCalculus . runTricuTEnv env
+
+runTricuTEnv :: Env -> String -> T
+runTricuTEnv env input =
+  let asts     = parseTricu input
+      finalEnv = evalTricu env asts
+   in result finalEnv
+
+runTricuWithEnvT :: String -> (Env, T)
+runTricuWithEnvT input =
+  let asts     = parseTricu input
+      finalEnv = evalTricu Map.empty asts
+   in (finalEnv, result finalEnv)
+
+runTricuWithEnv :: String -> (Env, String)
+runTricuWithEnv input =
+  let asts     = parseTricu input
+      finalEnv = evalTricu Map.empty asts
+      res      = result finalEnv
+   in (finalEnv, formatT TreeCalculus res)
+
+runTricuEnvWithEnvT :: Env -> String -> (Env, T)
+runTricuEnvWithEnvT env input =
+  let asts     = parseTricu input
+      finalEnv = evalTricu env asts
+   in (finalEnv, result finalEnv)
+
+runTricuEnvWithEnv :: Env -> String -> (Env, String)
+runTricuEnvWithEnv env input =
+  let asts     = parseTricu input
+      finalEnv = evalTricu env asts
+      res      = result finalEnv
+   in (finalEnv, formatT TreeCalculus res)
+
+chooseExportName :: String -> String -> [Text] -> IO Text
+chooseExportName explicitName input storedNames
+  | not (null explicitName) = return $ T.pack explicitName
+  | Just firstName <- firstNonEmpty storedNames = return firstName
+  | otherwise = do
+      hPutStrLn stderr $
+        "No stored name found for export target " ++ input ++ "; using export name 'root'. "
+        ++ "Use export -n NAME to preserve a semantic name."
+      return "root"
+
+firstNonEmpty :: [Text] -> Maybe Text
+firstNonEmpty = go
+  where
+    go [] = Nothing
+    go (x:xs)
+      | T.null x = go xs
+      | otherwise = Just x

src/Parser.hs

@@ -3,12 +3,12 @@ module Parser where
 import Lexer
 import Research
 
-import Control.Monad (void)
+import Control.Monad             (void)
 import Control.Monad.State
-import Data.List.NonEmpty (toList)
-import Data.Void (Void)
+import Data.List.NonEmpty        (toList)
+import Data.Void                 (Void)
 import Text.Megaparsec
-import Text.Megaparsec.Error (ParseErrorBundle, errorBundlePretty)
+
 import qualified Data.Set as Set
 
 data PState = PState
@@ -20,9 +20,9 @@ type ParserM = StateT PState (Parsec Void [LToken])
 
 satisfyM :: (LToken -> Bool) -> ParserM LToken
 satisfyM f = do
-  token <- lift (satisfy f)
-  modify' (updateDepth token)
-  return token
+  tok <- lift (satisfy f)
+  modify' (updateDepth tok)
+  return tok
 
 updateDepth :: LToken -> PState -> PState
 updateDepth LOpenParen    st = st { parenDepth   = parenDepth st   + 1 }
@@ -39,12 +39,12 @@ topLevelNewline = do
     else fail "Top-level exit in nested context (paren or bracket)"
 
 parseProgram :: [LToken] -> Either (ParseErrorBundle [LToken] Void) [TricuAST]
-parseProgram tokens =
-  runParser (evalStateT (parseProgramM <* finalizeDepth <* eof) (PState 0 0)) "" tokens
+parseProgram toks =
+  runParser (evalStateT (parseProgramM <* finalizeDepth <* eof) (PState 0 0)) "" toks
 
 parseSingleExpr :: [LToken] -> Either (ParseErrorBundle [LToken] Void) TricuAST
-parseSingleExpr tokens =
-  runParser (evalStateT (scnParserM *> parseExpressionM <* finalizeDepth <* eof) (PState 0 0)) "" tokens
+parseSingleExpr toks =
+  runParser (evalStateT (scnParserM *> parseExpressionM <* finalizeDepth <* eof) (PState 0 0)) "" toks
 
 finalizeDepth :: ParserM ()
 finalizeDepth = do
@@ -130,7 +130,6 @@ parseFunctionM = do
 parseLambdaM :: ParserM TricuAST
 parseLambdaM = do
   let ident = (\case LIdentifier _ -> True; _ -> False)
-  _      <- satisfyM (== LBackslash)
   params <- some (satisfyM ident)
   _      <- satisfyM (== LColon)
   scnParserM
@@ -145,11 +144,11 @@ parseLambdaExpressionM = choice
 
 parseAtomicLambdaM :: ParserM TricuAST
 parseAtomicLambdaM = choice
-  [ parseVarM
+  [ try parseLambdaM
+  , parseVarM
   , parseTreeLeafM
   , parseLiteralM
   , parseListLiteralM
-  , try parseLambdaM
   , between (satisfyM (== LOpenParen)) (satisfyM (== LCloseParen)) parseLambdaExpressionM
   ]
 
@@ -196,6 +195,7 @@ parseTreeTermM = do
       | TLeaf     <- acc = TStem next
       | TStem t   <- acc = TFork t next
       | TFork _ _ <- acc = TFork acc next
+      | otherwise        = SApp acc next
 
 parseTreeLeafOrParenthesizedM :: ParserM TricuAST
 parseTreeLeafOrParenthesizedM = choice
@@ -205,7 +205,8 @@ parseTreeLeafOrParenthesizedM = choice
 
 parseAtomicM :: ParserM TricuAST
 parseAtomicM = choice
-  [ parseVarM
+  [ try parseLambdaM
+  , parseVarM
   , parseTreeLeafM
   , parseListLiteralM
   , parseGroupedM
@@ -248,42 +249,51 @@ parseGroupedItemM = do
 
 parseSingleItemM :: ParserM TricuAST
 parseSingleItemM = do
-  token <- satisfyM (\case LIdentifier _ -> True; LKeywordT -> True; _ -> False)
-  if | LIdentifier name <- token -> pure (SVar name)
-     | token == LKeywordT        -> pure TLeaf
+  tok <- satisfyM (\case LIdentifier _ -> True; LKeywordT -> True; _ -> False)
+  if | LIdentifier name <- tok -> pure (SVar name Nothing)
+     | tok == LKeywordT        -> pure TLeaf
      | otherwise                 -> fail "Unexpected token in list item"
 
 parseVarM :: ParserM TricuAST
 parseVarM = do
-  token <- satisfyM (\case
+  tok <- satisfyM (\case
     LNamespace _ -> True
     LIdentifier _ -> True
+    LIdentifierWithHash _ _ -> True
     _ -> False)
-  case token of
+
+  case tok of
     LNamespace ns -> do
       _ <- satisfyM (== LDot)
       LIdentifier name <- satisfyM (\case LIdentifier _ -> True; _ -> False)
-      pure $ SVar (ns ++ "." ++ name)
+      pure $ SVar (ns ++ "." ++ name) Nothing
+
     LIdentifier name
       | name == "t" || name == "!result" ->
         fail ("Reserved keyword: " ++ name ++ " cannot be assigned.")
-      | otherwise -> pure (SVar name)
+      | otherwise -> pure (SVar name Nothing)
+
+    LIdentifierWithHash name hash ->
+      if name == "t" || name == "!result"
+        then fail ("Reserved keyword: " ++ name ++ " cannot be assigned.")
+        else pure (SVar name (Just hash))
+
     _ -> fail "Unexpected token while parsing variable"
 
 parseIntLiteralM :: ParserM TricuAST
 parseIntLiteralM = do
   let intL = (\case LIntegerLiteral _ -> True; _ -> False)
-  token <- satisfyM intL
-  if | LIntegerLiteral value <- token ->
-       pure (SInt value)
+  tok <- satisfyM intL
+  if | LIntegerLiteral value <- tok ->
+       pure (SInt (fromIntegral value))
      | otherwise                      ->
        fail "Unexpected token while parsing integer literal"
 
 parseStrLiteralM :: ParserM TricuAST
 parseStrLiteralM = do
   let strL = (\case LStringLiteral _ -> True; _ -> False)
-  token <- satisfyM strL
-  if | LStringLiteral value <- token ->
+  tok <- satisfyM strL
+  if | LStringLiteral value <- tok ->
        pure (SStr value)
      | otherwise                     ->
        fail "Unexpected token while parsing string literal"
@@ -299,8 +309,8 @@ handleParseError bundle =
   in unlines ("Parse error(s) encountered:" : formattedErrors)
 
 formatError :: ParseError [LToken] Void -> String
-formatError (TrivialError offset unexpected expected) =
-  let unexpectedMsg = case unexpected of
+formatError (TrivialError offset msgUnexpected expected) =
+  let unexpectedMsg = case msgUnexpected of
         Just x  -> "unexpected token " ++ show x
         Nothing -> "unexpected end of input"
       expectedMsg = if null expected

src/REPL.hs

@@ -1,31 +1,62 @@
 module REPL where
 
+import ContentStore
 import Eval
 import FileEval
-import Lexer
+import Lexer ()
 import Parser
 import Research
+import Wire
 
-import Control.Exception         (SomeException, catch)
+import Control.Concurrent (forkIO, threadDelay, killThread, ThreadId)
+import Control.Exception         (SomeException, catch, displayException)
+import Control.Monad ()
+import Control.Monad (forever, when, forM_, foldM, unless)
+import Control.Monad.Catch       (handle)
 import Control.Monad.IO.Class    (liftIO)
-import Control.Monad.Catch       (handle, MonadCatch)
-import Control.Monad.Trans.Class (lift)
+import Control.Monad.Trans.Class ()
 import Control.Monad.Trans.Maybe (MaybeT(..), runMaybeT)
+import Data.ByteString ()
 import Data.Char                 (isSpace)
-import Data.List                 ( dropWhile
-                                 , dropWhileEnd
-                                 , isPrefixOf)
+
+import qualified Data.ByteString.Lazy as BL
+import Data.IORef (newIORef, readIORef, writeIORef)
+import Data.List                 (dropWhileEnd, isPrefixOf, find)
+import Data.Maybe (isJust, fromJust)
+import Data.Time (getCurrentTime, diffUTCTime)
+import Data.Time.Clock.POSIX (posixSecondsToUTCTime)
+import Data.Time.Format (formatTime, defaultTimeLocale)
+import Data.Version (showVersion)
+import Database.SQLite.Simple (Connection, Only(..), query)
+import Paths_tricu (version)
+import System.Console.ANSI (setSGR, SGR(..), ConsoleLayer(..), ColorIntensity(..), Color(..))
 import System.Console.Haskeline
+import System.Directory (doesFileExist, createDirectoryIfMissing)
+import System.FSNotify
+import System.FilePath (takeDirectory, (</>))
+import Text.Read (readMaybe)
 
 import qualified Data.Map as Map
+import qualified Data.Text as T
+import qualified Data.Text.IO as T ()
 
-repl :: Env -> IO ()
-repl env = runInputT settings (withInterrupt (loop env True))
+data REPLState = REPLState
+  { replForm :: EvaluatedForm
+  , replContentStore :: Maybe Connection
+  , replWatchedFile :: Maybe FilePath
+  , replSelectedVersions :: Map.Map String T.Text
+  , replWatcherThread :: Maybe ThreadId
+  }
+
+repl :: IO ()
+repl = do
+  conn <- ContentStore.initContentStore 
+  runInputT settings (withInterrupt (loop (REPLState Decode (Just conn) Nothing Map.empty Nothing)))
   where
     settings :: Settings IO
     settings = Settings
       { complete = completeWord Nothing " \t" completeCommands
-      , historyFile = Just ".tricu_history"
+      , historyFile = Just "~/.local/state/tricu/history"
       , autoAddHistory = True
       }
 
@@ -33,84 +64,605 @@ repl env = runInputT settings (withInterrupt (loop env True))
     completeCommands str = return $ map simpleCompletion $
       filter (str `isPrefixOf`) commands
       where
-        commands = ["!exit", "!decode", "!definitions", "!import"]
+        commands = [ "!exit"
+                   , "!output"
+                   , "!import"
+                   , "!clear"
+                   , "!reset"
+                   , "!help"
+                   , "!definitions"
+                   , "!watch"
+                   , "!refresh"
+                   , "!versions"
+                   , "!select"
+                   , "!tag"
+                   , "!export"
+                   , "!bundleimport"
+                   ]
 
-    loop :: Env -> Bool -> InputT IO ()
-    loop env decode = handle (interruptHandler env decode) $ do
+    loop :: REPLState -> InputT IO ()
+    loop state = handle (\Interrupt -> interruptHandler state Interrupt) $ do
       minput <- getInputLine "tricu < "
       case minput of
-        Nothing -> outputStrLn "Exiting tricu"
+        Nothing -> return ()
         Just s
-          | strip s == "" -> loop env decode
+          | strip s == "" -> loop state
           | strip s == "!exit" -> outputStrLn "Exiting tricu"
-          | strip s == "!decode" -> do
-              outputStrLn $ "Decoding " ++ (if decode then "disabled" else "enabled")
-              loop env (not decode)
-          | strip s == "!definitions" -> do
-              let defs = Map.keys $ Map.delete "!result" env
-              if null defs
-                then outputStrLn "No definitions discovered."
-                else do
-                  outputStrLn "Available definitions:"
-                  mapM_ outputStrLn defs
-              loop env decode
-          | "!import" `isPrefixOf` strip s -> handleImport env decode
-          | take 2 s == "--" -> loop env decode
+          | strip s == "!clear" -> do
+              liftIO $ putStr "\ESC[2J\ESC[H"
+              loop state
+          | strip s == "!reset" -> do
+              outputStrLn "Selected versions reset"
+              loop state { replSelectedVersions = Map.empty }
+          | strip s == "!help" -> do
+              outputStrLn $ "tricu version " ++ showVersion version
+              outputStrLn "Available commands:"
+              outputStrLn "  !exit        - Exit the REPL"
+              outputStrLn "  !clear       - Clear the screen"
+              outputStrLn "  !reset       - Reset preferences for selected versions"
+              outputStrLn "  !help        - Show tricu version and available commands"
+              outputStrLn "  !output      - Change output format (tree|fsl|ast|ternary|ascii|decode)"
+              outputStrLn "  !definitions - List all defined terms in the content store"
+              outputStrLn "  !import      - Import definitions from file to the content store"
+              outputStrLn "  !watch       - Watch a file for changes, evaluate terms, and store them"
+              outputStrLn "  !versions    - Show all versions of a term by name"
+              outputStrLn "  !select      - Select a specific version of a term for subsequent lookups"
+              outputStrLn "  !tag         - Add or update a tag for a term by hash or name"
+              outputStrLn "  !export      - Export a term bundle to file (hash, file)"
+              outputStrLn "  !bundleimport- Import a bundle file into the content store"
+              loop state
+          | strip s == "!output" -> handleOutput state
+          | strip s == "!definitions" -> handleDefinitions state
+          | "!import" `isPrefixOf` strip s -> handleImport state
+          | "!watch" `isPrefixOf` strip s -> handleWatch state
+          | strip s == "!refresh" -> handleRefresh state
+          | "!versions" `isPrefixOf` strip s -> handleVersions state
+          | "!select" `isPrefixOf` strip s -> handleSelect state
+          | "!tag" `isPrefixOf` strip s -> handleTag state
+          | "!export" `isPrefixOf` strip s -> handleExport state
+          | "!bundleimport" `isPrefixOf` strip s -> handleBundleImport state
+          | take 2 s == "--" -> loop state
           | otherwise -> do
-              newEnv <- liftIO $ processInput env s decode `catch` errorHandler env
-              loop newEnv decode
+              evalResult <- liftIO $ catch
+                (processInput state s)
+                (errorHandler state)
+              loop evalResult
 
-    handleImport :: Env -> Bool -> InputT IO ()
-    handleImport env decode = do
-      result <- runMaybeT $ do
-        let fileSettings = setComplete completeFilename defaultSettings
-        path <- MaybeT $ runInputT fileSettings $
-          getInputLineWithInitial "File path to load < " ("", "")
+    handleOutput :: REPLState -> InputT IO ()
+    handleOutput state = do
+      let formats = [Decode, TreeCalculus, FSL, AST, Ternary, Ascii]
+      outputStrLn "Available output formats:"
+      mapM_ (\(i, f) -> outputStrLn $ show (i :: Int) ++ ". " ++ show f)
+        (zip [1..] formats)
 
-        contents <- liftIO $ readFile (strip path)
+      evalResult <- runMaybeT $ do
+        input <- MaybeT $ getInputLine "Select output format (1-6) < "
+        case reads input of
+          [(n, "")] | n >= 1 && n <= 6 ->
+            return $ formats !! (n-1)
+          _ -> MaybeT $ return Nothing
 
-        if | Left err <- parseProgram (lexTricu contents) -> do
-               lift $ outputStrLn $ "Parse error: " ++ handleParseError err
-               MaybeT $ return Nothing
-           | Right ast <- parseProgram (lexTricu contents) -> do
-               ns <- MaybeT $ runInputT defaultSettings $
-                 getInputLineWithInitial "Namespace (or !Local for no namespace) < " ("", "")
+      case evalResult of
+        Nothing -> do
+          outputStrLn "Invalid selection. Keeping current output format."
+          loop state
+        Just newForm -> do
+          outputStrLn $ "Output format changed to: " ++ show newForm
+          loop state { replForm = newForm }
 
-               processedAst <- liftIO $ preprocessFile (strip path)
-               let namespacedAst | strip ns == "!Local" = processedAst
-                                | otherwise = nsDefinitions (strip ns) processedAst
-                   loadedEnv = evalTricu env namespacedAst
-               return loadedEnv
+    handleDefinitions :: REPLState -> InputT IO ()
+    handleDefinitions state = case replContentStore state of
+      Nothing -> do
+        liftIO $ printError "Content store not initialized"
+        loop state
+      Just conn -> do
+        terms <- liftIO $ ContentStore.listStoredTerms conn
+        
+        if null terms
+          then do
+            liftIO $ printWarning "No terms in content store."
+            loop state
+          else do
+            liftIO $ do
+              printSuccess $ "Content store contains " ++ show (length terms) ++ " terms:"
 
-      if | Nothing <- result -> do
-             outputStrLn "Import cancelled."
-             loop env decode
-         | Just loadedEnv <- result ->
-             loop (Map.delete "!result" loadedEnv) decode
+            let maxNameWidth = maximum $ map (length . T.unpack . termNames) terms
 
-    interruptHandler :: Env -> Bool -> Interrupt -> InputT IO ()
-    interruptHandler env decode _ = do
-      outputStrLn "Interrupted with CTRL+C\n\
-                  \You can use the !exit command or CTRL+D to exit"
-      loop env decode
+            forM_ terms $ \term -> do
+              let namesStr = T.unpack (termNames term)
+                  hash = termHash term
+                  padding = replicate (maxNameWidth - length namesStr) ' '
+                  
+              liftIO $ do
+                putStr "  "
+                printVariable namesStr
+                putStr padding
+                putStr " [hash: "
+                displayColoredHash hash
+                putStrLn "]"
+                
+                tags <- ContentStore.termToTags conn hash 
+                unless (null tags) $ displayTags tags
 
-    processInput :: Env -> String -> Bool -> IO Env
-    processInput env input decode = do
-      let asts   = parseTricu input
-          newEnv = evalTricu env asts
-      case Map.lookup "!result" newEnv of
-        Just r -> do
-          putStrLn $ "tricu > " ++
-            if decode
-              then decodeResult r
-              else show r
-        Nothing -> pure ()
-      return newEnv
+            loop state
 
-    errorHandler :: Env -> SomeException -> IO (Env)
-    errorHandler env e = do
-      putStrLn $ "Error: " ++ show e
-      return env
+    handleImport :: REPLState -> InputT IO ()
+    handleImport state = do
+      let fset = setComplete completeFilename defaultSettings
+      filename <- runInputT fset $ getInputLineWithInitial "File to import: " ("", "")
+      case filename of
+        Nothing -> loop state
+        Just f -> do
+          let cleanFilename = strip f
+          exists <- liftIO $ doesFileExist cleanFilename
+          if not exists
+            then do
+              liftIO $ printError $ "File not found: " ++ cleanFilename
+              loop state
+            else importFile state cleanFilename
+
+    importFile :: REPLState -> String -> InputT IO ()
+    importFile state cleanFilename = do
+      _code <- liftIO $ readFile cleanFilename
+      case replContentStore state of
+        Nothing -> do
+          liftIO $ printError "Content store not initialized"
+          loop state
+        Just conn -> do
+          env <- liftIO $ evaluateFile cleanFilename
+          
+          liftIO $ do
+            printSuccess $ "Importing file: " ++ cleanFilename
+            let defs = Map.toList $ Map.delete "!result" env
+            
+            importedCount <- foldM (\count (name, term) -> do
+              hash <- ContentStore.storeTerm conn [name] term
+              printSuccess $ "Stored definition: " ++ name ++ " with hash " ++ T.unpack hash
+              return (count + (1 :: Int))
+              ) 0 defs
+            
+            printSuccess $ "Imported " ++ show importedCount ++ " definitions successfully"
+          
+          loop state
+
+    handleWatch :: REPLState -> InputT IO ()
+    handleWatch state = do
+      dbPath <- liftIO ContentStore.getContentStorePath
+      let filepath = takeDirectory dbPath </> "scratch.tri"
+      let dirPath = takeDirectory filepath
+
+      liftIO $ createDirectoryIfMissing True dirPath
+
+      fileExists <- liftIO $ doesFileExist filepath
+      unless fileExists $ liftIO $ writeFile filepath "-- tricu scratch file\n\n"
+
+      outputStrLn $ "Using scratch file: " ++ filepath
+
+      when (isJust (replWatcherThread state)) $ do
+        outputStrLn "Stopping previous file watch"
+        liftIO $ killThread (fromJust $ replWatcherThread state)
+
+      outputStrLn $ "Starting to watch file: " ++ filepath
+      outputStrLn "Press Ctrl+C to stop watching and return to REPL"
+
+      liftIO $ processWatchedFile filepath (replContentStore state) (replSelectedVersions state) (replForm state)
+
+      lastProcessedRef <- liftIO $ newIORef =<< getCurrentTime
+
+      watcherId <- liftIO $ forkIO $ withManager $ \mgr -> do
+        _stopAction <- watchDir mgr dirPath (\ev -> eventPath ev == filepath) $ \_ -> do
+          now <- getCurrentTime
+          lastProcessed <- readIORef lastProcessedRef
+          when (diffUTCTime now lastProcessed > 0.5) $ do
+            putStrLn $ "\nFile changed: " ++ filepath
+            processWatchedFile filepath (replContentStore state) (replSelectedVersions state) (replForm state)
+            writeIORef lastProcessedRef now
+        forever $ threadDelay 1000000
+
+      watchLoop state { replWatchedFile = Just filepath, replWatcherThread = Just watcherId }
+
+    _handleUnwatch :: REPLState -> InputT IO ()
+    _handleUnwatch state = case replWatchedFile state of
+      Nothing -> do
+        outputStrLn "No file is currently being watched"
+        loop state
+      Just path -> do
+        outputStrLn $ "Stopped watching " ++ path
+        when (isJust (replWatcherThread state)) $ do
+          liftIO $ killThread (fromJust $ replWatcherThread state)
+        loop state { replWatchedFile = Nothing, replWatcherThread = Nothing }
+
+    handleRefresh :: REPLState -> InputT IO ()
+    handleRefresh state = case replContentStore state of
+      Nothing -> do
+        outputStrLn "Content store not initialized"
+        loop state
+      Just _conn -> do
+        outputStrLn "Environment refreshed from content store (definitions are live)"
+        loop state
+
+    handleVersions :: REPLState -> InputT IO ()
+    handleVersions state = case replContentStore state of
+      Nothing -> do
+        liftIO $ printError "Content store not initialized"
+        loop state
+      Just conn -> do
+        liftIO $ printPrompt "Term name: "
+        nameInput <- getInputLine ""
+        case nameInput of
+          Nothing -> loop state
+          Just n -> do
+            let termName = strip n
+            versions <- liftIO $ ContentStore.termVersions conn termName
+            if null versions
+              then liftIO $ printError $ "No versions found for term: " ++ termName
+              else do
+                liftIO $ do
+                  printKeyword "Versions of "
+                  printVariable termName
+                  putStrLn ":"
+                  
+                  forM_ (zip [1..] versions) $ \(i, (hash, _, ts)) -> do
+                    tags <- ContentStore.termToTags conn hash
+                    putStr $ show (i :: Int) ++ ". "
+                    displayColoredHash hash
+                    putStr $ " (" ++ formatTimestamp ts ++ ")"
+                    unless (null tags) $ do
+                      putStr " ["
+                      printKeyword "Tags: "
+                      forM_ (zip [0..] tags) $ \(j, tag) -> do
+                        printTag (T.unpack tag)
+                        when (j < length tags - 1) $ putStr ", "
+                      putStr "]"
+                    putStrLn ""
+        loop state
+
+    handleSelect :: REPLState -> InputT IO ()
+    handleSelect state = case replContentStore state of
+      Nothing -> do
+        liftIO $ printError "Content store not initialized"
+        loop state
+      Just conn -> do
+        liftIO $ printPrompt "Term name: "
+        nameInput <- getInputLine ""
+        case nameInput of
+          Nothing -> loop state
+          Just n -> do
+            let cleanName = strip n
+            versions <- liftIO $ ContentStore.termVersions conn cleanName
+            if null versions
+              then do
+                liftIO $ printError $ "No versions found for term: " ++ cleanName
+                loop state
+              else do
+                liftIO $ do
+                  printKeyword "Versions of "
+                  printVariable cleanName
+                  putStrLn ":"
+                  
+                  forM_ (zip [1..] versions) $ \(i, (hash, _, ts)) -> do
+                    tags <- ContentStore.termToTags conn hash
+                    putStr $ show (i :: Int) ++ ". "
+                    displayColoredHash hash
+                    putStr $ " (" ++ formatTimestamp ts ++ ")"
+                    unless (null tags) $ do
+                      putStr " ["
+                      printKeyword "Tags: "
+                      forM_ (zip [0..] tags) $ \(j, tag) -> do
+                        printTag (T.unpack tag)
+                        when (j < length tags - 1) $ putStr ", "
+                      putStr "]"
+                    putStrLn ""
+
+                liftIO $ printPrompt "Select version (number or full hash, Enter to cancel): "
+                choiceInput <- getInputLine ""
+                let choice = strip <$> choiceInput
+
+                selectedHash <- case choice of
+                    Just selectedStr | not (null selectedStr) -> do
+                        case readMaybe selectedStr :: Maybe Int of
+                            Just idx | idx > 0 && idx <= length versions -> do
+                                let (h, _, _) = versions !! (idx - 1)
+                                return $ Just h
+                            _ -> do
+                                let potentialHash = T.pack selectedStr
+                                let foundByHash = find (\(h, _, _) -> T.isPrefixOf potentialHash h) versions
+                                case foundByHash of
+                                    Just (h, _, _) -> return $ Just h
+                                    Nothing -> do
+                                        liftIO $ printError "Invalid selection or hash not found in list."
+                                        return Nothing
+                    _ -> return Nothing
+
+                case selectedHash of
+                    Just hashToSelect -> do
+                        let newState = state { replSelectedVersions =
+                                              Map.insert cleanName hashToSelect (replSelectedVersions state) }
+                        liftIO $ do
+                          printSuccess "Selected version "
+                          displayColoredHash hashToSelect
+                          putStr " for term "
+                          printVariable cleanName
+                          putStrLn ""
+                        loop newState
+                    Nothing -> loop state
+
+    handleTag :: REPLState -> InputT IO ()
+    handleTag state = case replContentStore state of
+      Nothing -> do
+        liftIO $ printError "Content store not initialized"
+        loop state
+      Just conn -> do
+        liftIO $ printPrompt "Term hash (full or prefix) or name (most recent version will be used): "
+        identInput <- getInputLine ""
+        case identInput of
+          Nothing -> loop state
+          Just ident -> do
+            let cleanIdent = strip ident
+            
+            mFullHash <- liftIO $ resolveIdentifierToHash conn cleanIdent
+
+            case mFullHash of
+              Nothing -> do
+                liftIO $ printError $ "Could not resolve identifier: " ++ cleanIdent
+                loop state
+              Just fullHash -> do
+                liftIO $ do
+                    putStr "Tagging term with hash: "
+                    displayColoredHash fullHash
+                    putStrLn ""
+                tags <- liftIO $ ContentStore.termToTags conn fullHash
+                unless (null tags) $ do
+                  liftIO $ do
+                    printKeyword "Existing tags:"
+                    displayTags tags
+
+                liftIO $ printPrompt "Tag to add/set: "
+                tagValueInput <- getInputLine ""
+                case tagValueInput of
+                  Nothing -> loop state
+                  Just tv -> do
+                    let tagVal = T.pack (strip tv)
+                    liftIO $ do
+                      ContentStore.setTag conn fullHash tagVal 
+                      printSuccess $ "Tag '"
+                      printTag (T.unpack tagVal)
+                      putStr "' set for term with hash "
+                      displayColoredHash fullHash
+                      putStrLn ""
+                    loop state
+
+    resolveIdentifierToHash :: Connection -> String -> IO (Maybe T.Text)
+    resolveIdentifierToHash conn ident
+        | T.pack "#" `T.isInfixOf` T.pack ident = do
+            let hashPrefix = T.pack ident
+            matchingHashes <- liftIO $ query conn "SELECT hash FROM terms WHERE hash LIKE ?" (Only (hashPrefix <> "%")) :: IO [Only T.Text]
+            case matchingHashes of
+                [Only fullHash] -> return $ Just fullHash
+                [] -> do printError $ "No hash found starting with: " ++ T.unpack hashPrefix; return Nothing
+                _  -> do printError $ "Ambiguous hash prefix: " ++ T.unpack hashPrefix; return Nothing
+        | otherwise = do
+            versions <- ContentStore.termVersions conn ident
+            if null versions
+            then do printError $ "No versions found for term name: " ++ ident; return Nothing
+            else return $ Just $ (\(h,_,_) -> h) $ head versions
+
+    handleExport :: REPLState -> InputT IO ()
+    handleExport state = do
+      let fset = setComplete completeFilename defaultSettings
+      hashInput <- runInputT fset $ getInputLineWithInitial "Hash or name: " ("", "")
+      case hashInput of
+        Nothing -> loop state
+        Just hashStr -> do
+          fileInput <- runInputT fset $ getInputLineWithInitial "Output file: " ("", "")
+          case fileInput of
+            Nothing -> loop state
+            Just outFile -> case replContentStore state of
+              Nothing -> do
+                liftIO $ printError "Content store not initialized"
+                loop state
+              Just conn -> do
+                let cleanHash = strip hashStr
+                hash <- liftIO $ do
+                  let h = T.pack cleanHash
+                  if '#' `T.elem` h
+                    then return h
+                    else do
+                      results <- query conn "SELECT hash FROM terms WHERE names LIKE ? LIMIT 1"
+                        (Only (h <> "%")) :: IO [Only T.Text]
+                      case results of
+                        [Only fullHash] -> return fullHash
+                        [] -> do
+                          results2 <- query conn "SELECT hash FROM terms WHERE hash LIKE ? LIMIT 1"
+                            (Only (h <> "%")) :: IO [Only T.Text]
+                          case results2 of
+                            [Only fullHash] -> return fullHash
+                            _ -> do
+                              printError $ "No term found matching: " ++ cleanHash
+                              return h
+                        _ -> do
+                          printError $ "Ambiguous match for: " ++ cleanHash
+                          return h
+                bundleData <- liftIO $ exportBundle conn [hash]
+                liftIO $ BL.writeFile outFile (BL.fromStrict bundleData)
+                liftIO $ do
+                  printSuccess $ "Exported bundle with root "
+                  displayColoredHash hash
+                  putStrLn $ " to " ++ outFile
+                loop state
+
+    handleBundleImport :: REPLState -> InputT IO ()
+    handleBundleImport state = do
+      let fset = setComplete completeFilename defaultSettings
+      fileInput <- runInputT fset $ getInputLineWithInitial "Bundle file: " ("", "")
+      case fileInput of
+        Nothing -> loop state
+        Just inFile -> case replContentStore state of
+          Nothing -> do
+            liftIO $ printError "Content store not initialized"
+            loop state
+          Just conn -> do
+            exists <- liftIO $ doesFileExist inFile
+            if not exists
+              then do
+                liftIO $ printError $ "File not found: " ++ inFile
+                loop state
+              else do
+                bundleData <- liftIO $ BL.readFile inFile
+                roots <- liftIO $ importBundle conn (BL.toStrict bundleData)
+                liftIO $ do
+                  printSuccess $ "Imported " ++ show (length roots) ++ " root(s):"
+                  mapM_ (\r -> putStrLn $ "  " ++ T.unpack r) roots
+                loop state
+
+    interruptHandler :: REPLState -> Interrupt -> InputT IO ()
+    interruptHandler state _ = do
+      liftIO $ do
+        printWarning "Interrupted with CTRL+C"
+        printWarning "You can use the !exit command or CTRL+D to exit"
+      loop state
+
+    errorHandler :: REPLState -> SomeException -> IO REPLState
+    errorHandler state e = do
+      printError $ "Error: " ++ displayException e
+      return state
+
+    processInput :: REPLState -> String -> IO REPLState
+    processInput state input = do
+      let asts = parseTricu input
+      case asts of
+        [] -> return state
+        _ -> case replContentStore state of
+          Nothing -> do
+            printError "Content store not initialized"
+            return state
+          Just conn -> do
+            newState <- foldM (\s astNode -> do
+              let varsInAst = Eval.findVarNames astNode
+              foldM (\currentSelectionState varName ->
+                if Map.member varName (replSelectedVersions currentSelectionState)
+                  then return currentSelectionState
+                  else do
+                    versions <- ContentStore.termVersions conn varName
+                    if length versions > 1
+                      then do
+                        let (latestHash, _, _) = head versions
+                        liftIO $ printWarning $ "Multiple versions of '" ++ varName ++ "' found. Using most recent."
+                        return currentSelectionState { replSelectedVersions = Map.insert varName latestHash (replSelectedVersions currentSelectionState) }
+                      else return currentSelectionState
+                ) s varsInAst
+              ) state asts
+
+            forM_ asts $ \ast -> do
+              case ast of
+                SDef name [] body -> do
+                  evalResult <- evalAST (Just conn) (replSelectedVersions newState) body
+                  hash <- ContentStore.storeTerm conn [name] evalResult
+                  
+                  liftIO $ do
+                    putStr "tricu > "
+                    printSuccess "Stored definition: "
+                    printVariable name
+                    putStr " with hash "
+                    displayColoredHash hash
+                    putStrLn ""
+                    
+                    putStr "tricu > "
+                    printResult $ formatT (replForm newState) evalResult
+                    putStrLn ""
+
+                _ -> do
+                  evalResult <- evalAST (Just conn) (replSelectedVersions newState) ast
+                  liftIO $ do
+                    putStr "tricu > "
+                    printResult $ formatT (replForm newState) evalResult
+                    putStrLn ""
+            return newState
 
     strip :: String -> String
     strip = dropWhileEnd isSpace . dropWhile isSpace
+
+    watchLoop :: REPLState -> InputT IO ()
+    watchLoop state = handle (\Interrupt -> do
+                                outputStrLn "\nStopped watching file"
+                                when (isJust (replWatcherThread state)) $ do
+                                  liftIO $ killThread (fromJust $ replWatcherThread state)
+                                loop state { replWatchedFile = Nothing, replWatcherThread = Nothing }) $ do
+      liftIO $ threadDelay 1000000
+      watchLoop state
+
+    processWatchedFile :: FilePath -> Maybe Connection -> Map.Map String T.Text -> EvaluatedForm -> IO ()
+    processWatchedFile filepath mconn selectedVersions outputForm = do
+      content <- readFile filepath
+      let asts = parseTricu content
+
+      case mconn of
+        Nothing -> putStrLn "Content store not initialized for watched file processing."
+        Just conn -> do
+          forM_ asts $ \ast -> case ast of
+            SDef name [] body -> do
+              evalResult <- evalAST (Just conn) selectedVersions body
+              hash <- ContentStore.storeTerm conn [name] evalResult
+              putStrLn $ "tricu > Stored definition: " ++ name ++ " with hash " ++ T.unpack hash
+              putStrLn $ "tricu > " ++ name ++ " = " ++ formatT outputForm evalResult
+            _ -> do
+              evalResult <- evalAST (Just conn) selectedVersions ast
+              putStrLn $ "tricu > Result: " ++ formatT outputForm evalResult
+          putStrLn $ "tricu > Processed file: " ++ filepath
+
+    formatTimestamp :: Integer -> String
+    formatTimestamp ts = formatTime defaultTimeLocale "%Y-%m-%d %H:%M:%S" (posixSecondsToUTCTime (fromIntegral ts))
+
+    displayColoredHash :: T.Text -> IO ()
+    displayColoredHash hash = do
+      let (prefix, rest) = T.splitAt 16 hash
+      setSGR [SetColor Foreground Vivid Cyan]
+      putStr $ T.unpack prefix
+      setSGR [SetColor Foreground Dull White]
+      putStr $ T.unpack rest
+      setSGR [Reset]
+
+    withColor :: ColorIntensity -> Color -> IO () -> IO ()
+    withColor intensity color action = do
+      setSGR [SetColor Foreground intensity color]
+      action
+      setSGR [Reset]
+
+    printColored :: ColorIntensity -> Color -> String -> IO ()
+    printColored intensity color text = withColor intensity color $ putStr text
+
+    printlnColored :: ColorIntensity -> Color -> String -> IO ()
+    printlnColored intensity color text = withColor intensity color $ putStrLn text
+
+    printSuccess :: String -> IO ()
+    printSuccess = printlnColored Vivid Green
+
+    printError :: String -> IO ()
+    printError = printlnColored Vivid Red
+
+    printWarning :: String -> IO ()
+    printWarning = printlnColored Vivid Yellow
+
+    printPrompt :: String -> IO ()
+    printPrompt = printColored Vivid Blue
+
+    printVariable :: String -> IO ()
+    printVariable = printColored Vivid Magenta
+
+    printTag :: String -> IO ()
+    printTag = printColored Vivid Yellow
+
+    printKeyword :: String -> IO ()
+    printKeyword = printColored Vivid Blue
+
+    printResult :: String -> IO ()
+    printResult = printColored Dull White
+
+    displayTags :: [T.Text] -> IO ()
+    displayTags [] = return ()
+    displayTags tags = do
+      putStr "    Tags: "
+      forM_ (zip [0..] tags) $ \(i, tag) -> do
+        printTag (T.unpack tag)
+        when (i < length tags - 1) $ putStr ", "
+      putStrLn ""

src/Research.hs

@@ -1,13 +1,19 @@
 module Research where
 
-import Control.Monad.State
+import Crypto.Hash               (hash, SHA256, Digest)
+import Data.ByteArray            (convert)
+import Data.ByteString.Base16    (decode, encode)
 import Data.List                 (intercalate)
-import Data.Map                  (Map)
+import Data.Map                  ()
 import Data.Text                 (Text, replace)
+import Data.Text.Encoding        (decodeUtf8, encodeUtf8)
+import Data.Word                 (Word8)
 import System.Console.CmdArgs    (Data, Typeable)
 
+import qualified Data.ByteString as BS
 import qualified Data.Map        as Map
-import qualified Data.Text as T
+import qualified Data.Set        as Set
+import qualified Data.Text       as T
 
 -- Tree Calculus Types
 data T = Leaf | Stem T | Fork T T
@@ -15,8 +21,8 @@ data T = Leaf | Stem T | Fork T T
 
 -- Abstract Syntax Tree for tricu
 data TricuAST
-  = SVar String
-  | SInt Int
+  = SVar String (Maybe String)
+  | SInt Integer
   | SStr String
   | SList [TricuAST]
   | SDef String [String] TricuAST
@@ -31,22 +37,22 @@ data TricuAST
 
 -- Lexer Tokens
 data LToken
-  = LKeywordT
-  | LIdentifier String
+  = LIdentifier String
+  | LIdentifierWithHash String String
+  | LKeywordT
   | LNamespace String
-  | LIntegerLiteral Int
-  | LStringLiteral String
+  | LImport String String
   | LAssign
   | LColon
   | LDot
-  | LBackslash
   | LOpenParen
   | LCloseParen
   | LOpenBracket
   | LCloseBracket
+  | LStringLiteral String
+  | LIntegerLiteral Int
   | LNewline
-  | LImport String String
-  deriving (Show, Eq, Ord)
+  deriving (Eq, Show, Ord)
 
 -- Output formats
 data EvaluatedForm = TreeCalculus | FSL | AST | Ternary | Ascii | Decode
@@ -55,15 +61,139 @@ data EvaluatedForm = TreeCalculus | FSL | AST | Ternary | Ascii | Decode
 -- Environment containing previously evaluated TC terms
 type Env = Map.Map String T
 
--- Tree Calculus Reduction
+-- Merkle DAG Node types
+-- Each Tree Calculus node becomes a content-addressed object.
+
+type MerkleHash = Text
+
+data Node
+  = NLeaf
+  | NStem MerkleHash
+  | NFork MerkleHash MerkleHash
+  deriving (Show, Eq, Ord)
+
+-- | Canonical serialization of a Node for hashing.
+--   Leaf:  0x00
+--   Stem:  0x01 || child_hash (32 bytes)
+--   Fork:  0x02 || left_hash (32 bytes) || right_hash (32 bytes)
+serializeNode :: Node -> BS.ByteString
+serializeNode NLeaf        = BS.pack [0x00]
+serializeNode (NStem h) = BS.pack [0x01] <> go (decode (encodeUtf8 h))
+  where go (Left _) = error "Research.serializeNode: invalid hex hash"
+        go (Right bs) = bs
+serializeNode (NFork l r) = BS.pack [0x02] <> go (decode (encodeUtf8 l)) <> go (decode (encodeUtf8 r))
+  where go (Left _) = error "Research.serializeNode: invalid hex hash"
+        go (Right bs) = bs
+
+-- | Hash a node per the Merkle content-addressing spec.
+-- hash = SHA256( "arboricx.merkle.node.v1" <> 0x00 <> node_payload )
+nodeHash :: Node -> MerkleHash
+nodeHash node = decodeUtf8 (encode (sha256WithPrefix (serializeNode node)))
+  where sha256WithPrefix payload =
+          convert . (hash :: BS.ByteString -> Digest SHA256) $ utf8Tag <> BS.pack [0x00] <> payload
+        utf8Tag = BS.pack $ map fromIntegral $ BS.unpack "arboricx.merkle.node.v1"
+
+-- | Deserialize a Node from canonical bytes.
+deserializeNode :: BS.ByteString -> Node
+deserializeNode bs =
+  case BS.uncons bs of
+    Just (0x00, rest)
+      | BS.null rest -> NLeaf
+
+    Just (0x01, rest)
+      | BS.length rest == 32 ->
+          NStem $ decodeUtf8 (encode rest)
+
+    Just (0x02, rest)
+      | BS.length rest == 64 ->
+          let (l, r) = BS.splitAt 32 rest
+          in NFork (decodeUtf8 (encode l)) (decodeUtf8 (encode r))
+
+    _ -> errorWithoutStackTrace "invalid merkle node payload"
+
+-- ---------------------------------------------------------------------------
+-- ByteString / bytestream marshalling via existing Tree Calculus conventions
+-- ---------------------------------------------------------------------------
+
+-- | Encode a single byte (Word8) as a Tree Calculus number (0..255).
+ofByte :: Word8 -> T
+ofByte = ofNumber . fromIntegral
+
+-- | Decode a Tree Calculus number as a single byte (Word8).
+--   Rejects values outside the range 0..255.
+toByte :: T -> Either String Word8
+toByte t = case toNumber t of
+  Left err -> Left err
+  Right n
+    | n >= 0 && n <= 255 -> Right (fromIntegral n)
+    | otherwise -> Left ("Byte value out of range: " ++ show n)
+
+-- | Encode a ByteString as a Tree Calculus list of Byte trees.
+ofBytes :: BS.ByteString -> T
+ofBytes = ofList . map ofByte . BS.unpack
+
+-- | Decode a Tree Calculus list of Byte trees as a ByteString.
+--   Rejects non-list trees and elements that are not valid byte values (0..255).
+toBytes :: T -> Either String BS.ByteString
+toBytes t = case toList t of
+  Left err -> Left err
+  Right bs -> BS.pack <$> mapM toByte bs
+
+-- | Convert a canonical Arboricx node payload (ByteString) to a Tree
+--   representation (a list of Byte trees).
+nodePayloadToTreeBytes :: BS.ByteString -> T
+nodePayloadToTreeBytes = ofBytes
+
+-- | Convert a Tree representation of a node payload back to ByteString.
+treeBytesToNodePayload :: T -> Either String BS.ByteString
+treeBytesToNodePayload = toBytes
+
+-- | Convert a MerkleHash (hex-encoded) to a Tree of its 32 raw bytes.
+hashToTreeBytes :: MerkleHash -> Either String T
+hashToTreeBytes h = case decode (encodeUtf8 h) of
+  Left _  -> Left "Invalid hex MerkleHash"
+  Right raw
+    | BS.length raw == 32 -> Right (ofBytes raw)
+    | otherwise -> Left "Hash raw bytes must be 32 bytes"
+
+-- | Convert a Tree of 32 Byte trees back to a MerkleHash (hex string).
+treeBytesToHash :: T -> Either String MerkleHash
+treeBytesToHash t = case toList t of
+  Left err -> Left err
+  Right bytes
+    | length bytes == 32 -> do
+        raw <- BS.pack <$> mapM toByte bytes
+        Right $ decodeUtf8 (encode raw)
+    | otherwise -> Left "Expected exactly 32 byte elements for hash"
+
+-- | Build a Merkle DAG from a Tree Calculus term.
+buildMerkle :: T -> Node
+buildMerkle Leaf = NLeaf
+buildMerkle (Stem t) = NStem (nodeHash child)
+  where child = buildMerkle t
+buildMerkle (Fork l r) = NFork (nodeHash left) (nodeHash right)
+  where
+    left  = buildMerkle l
+    right = buildMerkle r
+
+-- Tree Calculus Reduction Rules
+{-
+  The t operator is left associative.
+  1.  t  t      a b       -> a
+  2.  t (t a)   b c       -> a c (b c)
+  3a. t (t a b) c t       -> a
+  3b. t (t a b) c (t u)   -> b u
+  3c. t (t a b) c (t u v) -> c u v
+-}
 apply :: T -> T -> T
-apply Leaf b                            = Stem b
-apply (Stem a) b                        = Fork a b
-apply (Fork Leaf a) _                   = a
-apply (Fork (Stem a1) a2) b             = apply (apply a1 b) (apply a2 b)
-apply (Fork (Fork a1 a2) a3) Leaf       = a1
-apply (Fork (Fork a1 a2) a3) (Stem u)   = apply a2 u
-apply (Fork (Fork a1 a2) a3) (Fork u v) = apply (apply a3 u) v
+apply (Fork Leaf a)         _         = a
+apply (Fork (Stem a) b) c             = apply (apply a c) (apply b c)
+apply (Fork (Fork _a _b) _c)  Leaf      = _a
+apply (Fork (Fork _a _b) _c) (Stem u)   = apply _b u
+apply (Fork (Fork _a _b) _c) (Fork u v) = apply (apply _c u) v
+-- Left associative `t`
+apply  Leaf b                         = Stem b
+apply (Stem a) b                      = Fork a b
 
 -- Booleans
 _false :: T
@@ -77,9 +207,9 @@ _not = Fork (Fork _true (Fork Leaf _false)) Leaf
 
 -- Marshalling
 ofString :: String -> T
-ofString str = ofList (map ofNumber (map fromEnum str))
+ofString str = ofList $ map (ofNumber . toInteger . fromEnum) str
 
-ofNumber :: Int -> T
+ofNumber :: Integer -> T
 ofNumber 0 = Leaf
 ofNumber n =
   Fork
@@ -87,10 +217,9 @@ ofNumber n =
     (ofNumber (n `div` 2))
 
 ofList :: [T] -> T
-ofList [] = Leaf
-ofList (x:xs) = Fork x (ofList xs)
+ofList = foldr Fork Leaf
 
-toNumber :: T -> Either String Int
+toNumber :: T -> Either String Integer
 toNumber Leaf = Right 0
 toNumber (Fork Leaf rest) = case toNumber rest of
   Right n -> Right (2 * n)
@@ -102,8 +231,8 @@ toNumber _ = Left "Invalid Tree Calculus number"
 
 toString :: T -> Either String String
 toString tc = case toList tc of
-  Right list -> traverse (fmap toEnum . toNumber) list
-  Left err -> Left "Invalid Tree Calculus string"
+  Right list -> traverse (fmap (toEnum . fromInteger) . toNumber) list
+  Left _ -> Left "Invalid Tree Calculus string"
 
 toList :: T -> Either String [T]
 toList Leaf = Right []
@@ -113,20 +242,20 @@ toList (Fork x rest) = case toList rest of
 toList _ = Left "Invalid Tree Calculus list"
 
 -- Outputs
-formatResult :: EvaluatedForm -> T -> String
-formatResult TreeCalculus = toSimpleT . show
-formatResult FSL          = show
-formatResult AST          = show . toAST
-formatResult Ternary      = toTernaryString
-formatResult Ascii        = toAscii
-formatResult Decode       = decodeResult
+formatT :: EvaluatedForm -> T -> String
+formatT TreeCalculus = toSimpleT . show
+formatT FSL          = show
+formatT AST          = show . toAST
+formatT Ternary      = toTernaryString
+formatT Ascii        = toAscii
+formatT Decode       = decodeResult
 
 toSimpleT :: String -> String
 toSimpleT s = T.unpack
   $ replace "Fork" "t"
   $ replace "Stem" "t"
   $ replace "Leaf" "t"
-  $ (T.pack s)
+  $ T.pack s
 
 toTernaryString :: T -> String
 toTernaryString Leaf = "0"
@@ -153,8 +282,56 @@ toAscii tree = go tree "" True
         ++ go right (prefix ++ (if isLast then "    " else "|   ")) True
 
 decodeResult :: T -> String
-decodeResult tc
-  | Right num  <- toNumber tc = show num
-  | Right str  <- toString tc = "\"" ++ str ++ "\""
-  | Right list <- toList tc   = "[" ++ intercalate ", " (map decodeResult list) ++ "]"
-  | otherwise                 = formatResult TreeCalculus tc
+decodeResult Leaf = "t"
+decodeResult tc =
+  case (toString tc, toList tc, toNumber tc) of
+    (Right s, _, _) | all isCommonChar s -> "\"" ++ s ++ "\""
+    (_, _, Right n) -> show n
+    (_, Right xs@(_:_), _) -> "[" ++ intercalate ", " (map decodeResult xs) ++ "]"
+    (_, Right [], _) -> "[]"
+    _ -> formatT TreeCalculus tc
+  where
+    isCommonChar c =
+      let n = fromEnum c
+      in (n >= 32 && n <= 126)
+         || n == 9
+         || n == 10
+         || n == 13
+
+-- ---------------------------------------------------------------------------
+-- DAG node-table export (for host-language kernel embedding)
+-- ---------------------------------------------------------------------------
+
+-- | Export a term's Merkle DAG as a topologically-sorted node table.
+-- Children appear before parents so all index references are forward.
+-- Returns (root index, list of (tag, [child_indices])).
+exportDag :: T -> (Int, [(String, [Int])])
+exportDag term =
+  let (root, acc, _) = collectDag term [] Set.empty
+      -- acc is in reverse post-order (children first, root last)
+      ordered = reverse acc
+      idxMap = Map.fromList [(h, i) | (i, (h, _)) <- zip [0..] ordered]
+      rootIdx = idxMap Map.! root
+      lines_ = map (formatNode idxMap . snd) ordered
+  in (rootIdx, lines_)
+  where
+    collectDag :: T -> [(MerkleHash, Node)] -> Set.Set MerkleHash -> (MerkleHash, [(MerkleHash, Node)], Set.Set MerkleHash)
+    collectDag Leaf acc seen =
+      let h = nodeHash NLeaf
+      in if Set.member h seen then (h, acc, seen) else (h, (h, NLeaf) : acc, Set.insert h seen)
+    collectDag (Stem t) acc seen =
+      let (ch, acc', seen') = collectDag t acc seen
+          node = NStem ch
+          h = nodeHash node
+      in if Set.member h seen' then (h, acc', seen') else (h, (h, node) : acc', Set.insert h seen')
+    collectDag (Fork l r) acc seen =
+      let (lh, acc', seen') = collectDag l acc seen
+          (rh, acc'', seen'') = collectDag r acc' seen'
+          node = NFork lh rh
+          h = nodeHash node
+      in if Set.member h seen'' then (h, acc'', seen'') else (h, (h, node) : acc'', Set.insert h seen'')
+
+    formatNode :: Map.Map MerkleHash Int -> Node -> (String, [Int])
+    formatNode _ NLeaf = ("leaf", [])
+    formatNode idxMap (NStem ch) = ("stem", [idxMap Map.! ch])
+    formatNode idxMap (NFork l r) = ("fork", [idxMap Map.! l, idxMap Map.! r])

src/Server.hs

@@ -0,0 +1,232 @@
+module Server
+  ( runServer
+  ) where
+
+import ContentStore (initContentStore, nameToTerm, hashToTerm, listStoredTerms,
+                     parseNameList, StoredTerm(..), termHash)
+import Database.SQLite.Simple (close)
+import Wire (exportNamedBundle)
+
+import Control.Monad (when)
+import Data.Maybe (catMaybes)
+import Control.Monad (void)
+
+import Network.HTTP.Types (Header, Status, status200, status400, status404, status405, hContentType)
+import Network.Wai
+import Network.Wai.Handler.Warp (defaultSettings, runSettings, setHost, setPort)
+
+import Data.String (fromString)
+import Data.Text (Text)
+import Data.Text.Encoding (encodeUtf8, decodeUtf8)
+import Data.Char (isHexDigit, toLower)
+import Data.ByteString.Char8 (unpack)
+import Data.ByteString.Lazy (fromStrict)
+import qualified Data.Text as T
+
+-- | Start an HTTP server that serves Arboricx bundles from the
+--   local content store.
+--
+-- This is a read-only export surface.  Clients fetch bundle bytes
+-- and independently inspect / verify / run them.  The server does
+-- not execute bundles.
+--
+-- Bind host defaults to @127.0.0.1@.
+--
+-- Endpoints
+-- ---------
+--   GET /health                           - 200 "ok"
+--   GET /bundle/name/:name                - export single term by name
+--   GET /bundle/hash/:hash                - export single term by hash
+--   GET /bundle/roots?n=...&h=...         - export multiple roots (n=name, h=hash)
+--   GET /terms                            - plain-text listing (debug)
+--
+runServer :: String -> Int -> IO ()
+runServer hostStr port =
+  runSettings settings app
+  where
+    settings = setPort port $ setHost (fromString hostStr) defaultSettings
+
+-- | WAI application backed by the content store.
+--   Uses the same database path as @eval@ mode (env var
+--   @TRICU_DB_PATH@ or the default location).
+app :: Application
+app request respond = case (requestMethod request, pathInfo request) of
+  ("GET", ["health"]) ->
+    respond $ healthResponse
+
+  ("GET", ["bundle", "roots"]) ->
+    rootsHandler request respond
+
+  ("GET", ["bundle", "name", nameText]) -> do
+    body <- nameHandler nameText
+    respond body
+
+  ("GET", ["bundle", "hash", hashText]) -> do
+    body <- hashHandler hashText
+    respond body
+
+  ("GET", ["terms"]) -> do
+    body <- termsResponse
+    respond body
+
+  ("POST", _) ->
+    respond $ responseLBS status405 [] "Method not allowed"
+
+  ("PUT", _) ->
+    respond $ responseLBS status405 [] "Method not allowed"
+
+  ("DELETE", _) ->
+    respond $ responseLBS status405 [] "Method not allowed"
+
+  _ ->
+    respond $ responseLBS status404 [] "not found"
+
+healthResponse :: Response
+healthResponse = responseLBS status200 [] "ok"
+
+-- | GET /bundle/roots?n=root&n=helper&h=abc123...
+--   Resolve multiple named roots (by stored term name or raw hash)
+--   and return a single bundle containing all of them.
+--
+--   Query parameters:
+--     - @n=<name>@ — one or more stored term names (resolved via nameToTerm)
+--     - @h=<hash>@ — one or more full Merkle hashes (validated as 16-64 hex chars)
+--
+--   The bundle manifest receives all resolved (name, hash) pairs as roots
+--   and exports. The node section is the union of all reachable nodes.
+rootsHandler :: Request -> (Response -> IO a) -> IO a
+rootsHandler request respond = do
+  conn <- initContentStore
+  let qs = queryString request
+      nParams = catMaybes [v | (k, v) <- qs, map toLower (unpack k) == "n"]
+      hParams = catMaybes [v | (k, v) <- qs, map toLower (unpack k) == "h"]
+  -- Resolve 'n' params to (name, hash) pairs
+  nResults <- mapM (\nVal -> do
+    stored <- nameToTerm conn (decodeUtf8 nVal)
+    case stored of
+      Nothing -> return Nothing
+      Just t  -> return $ Just (decodeUtf8 nVal, termHash t)) nParams
+  let namedHashesFromN = catMaybes nResults
+  -- Validate 'h' params and build (name, hash) pairs
+  namedHashesFromH <- mapM (\hVal -> do
+    let raw = T.pack (dropWhile (=='#') (T.unpack (decodeUtf8 hVal)))
+    if T.all isHexDigit raw && T.length raw >= 16
+      then do
+        stored <- hashToTerm conn raw
+        let names = maybe "root" firstOrRoot (termNames <$> stored)
+        return $ Just (names, raw)
+      else return Nothing)
+    hParams
+  let allNamedHashes = namedHashesFromN ++ catMaybes namedHashesFromH
+  -- Require at least one root
+  when (null allNamedHashes) $ do
+    let resp = responseLBS status400 [] "400 Bad Request: at least one n= or h= parameter required"
+    close conn
+    void $ respond resp
+  -- Build and return the bundle
+  bundleData <- exportNamedBundle conn allNamedHashes
+  let firstHash = snd (head allNamedHashes)
+      cd = T.pack "attachment; filename=roots.bundle"
+  close conn
+  respond $ responseLBS status200
+    (bundleHeaders firstHash cd)
+    (fromStrict bundleData)
+
+-- | GET /bundle/name/:name
+--   Resolve a stored term name, export it as an Arboricx bundle,
+--   and return the raw bundle bytes.
+--
+--   Sets @Content-Type@ and @X-Arboricx-Root-Hash@ headers.
+--   Returns 404 when the name does not resolve to any stored term.
+nameHandler :: Text -> IO Response
+nameHandler nameText = do
+  conn <- initContentStore
+  stored <- nameToTerm conn nameText
+  case stored of
+    Nothing -> do
+      close conn
+      return $ textResponse status404 ("not found: " <> nameText)
+    Just term' -> do
+      let th = termHash term'
+          namedHashes = [(firstOrRoot (termNames term'), th)]
+      bundleData <- exportNamedBundle conn namedHashes
+      let cd = T.pack $ "attachment; filename=" ++ safeFileName (T.unpack nameText) ++ ".bundle"
+      close conn
+      return $ responseLBS status200 (bundleHeaders th cd) (fromStrict bundleData)
+
+-- | GET /bundle/hash/:hash
+--   Resolve a full Merkle hash and export the root as an Arboricx
+--   bundle.
+--
+--   - Malformed hash (non-hex or < 16 chars): 400
+--   - Well-formed but absent: 404
+--   - Present: 200 with bundle bytes
+hashHandler :: Text -> IO Response
+hashHandler hashText =
+  let raw = T.pack (dropWhile (== '#') (T.unpack hashText))
+  in if not (T.all isHexDigit raw) || T.length raw < 16
+        then return $ responseLBS status400 [] "400 Bad Request: invalid hash"
+        else do
+          conn <- initContentStore
+          stored <- hashToTerm conn raw
+          case stored of
+            Nothing -> do
+              close conn
+              return $ textResponse status404 ("not found: " <> hashText)
+            Just term' -> do
+              let th = termHash term'
+                  namedHashes' = [(firstOrRoot (termNames term'), th)]
+              bundleData <- exportNamedBundle conn namedHashes'
+              close conn
+              return $ responseLBS status200
+                (bundleHeaders th "attachment; filename=hash.bundle")
+                (fromStrict bundleData)
+
+-- | GET /terms
+--   Plain-text listing of all stored terms (debugging only).
+termsResponse :: IO Response
+termsResponse = do
+  conn <- initContentStore
+  terms <- listStoredTerms conn
+  close conn
+  let lines' = [ names <> "  " <> hash <> "  " <> T.pack (show created)
+               | term <- terms
+               , let names = termNames term
+               , let hash = termHash term
+               , let created = termCreatedAt term ]
+  return $ responseLBS status200
+    [ (hContentType, encodeUtf8 "text/plain; charset=utf-8")
+    ]
+    (fromStrict $ encodeUtf8 $ T.unlines lines')
+
+textResponse :: Status -> Text -> Response
+textResponse status body =
+  responseLBS status
+    [ (hContentType, encodeUtf8 "text/plain; charset=utf-8") ]
+    (fromStrict $ encodeUtf8 body)
+
+bundleHeaders :: Text -> Text -> [Header]
+bundleHeaders root cd =
+  [ (hContentType, encodeUtf8 "application/vnd.arboricx.bundle")
+  , ("X-Arboricx-Root-Hash", encodeUtf8 root)
+  , ("Content-Disposition", encodeUtf8 cd)
+  ]
+
+-- | Pick the first stored name, falling back to "root" when names are empty.
+firstOrRoot :: Text -> Text
+firstOrRoot names =
+  case parseNameList names of
+    [] -> "root"
+    (x:_) -> x
+
+-- | Sanitise a string to a safe filename prefix.
+safeFileName :: String -> String
+safeFileName = map go
+  where
+    go c
+      | c >= 'a' && c <= 'z' = c
+      | c >= 'A' && c <= 'Z' = c
+      | c >= '0' && c <= '9' = c
+      | c == '-' = c
+      | c == '_' = c
+      | otherwise = '_'

src/Wire.hs

@@ -0,0 +1,973 @@
+{-# LANGUAGE DeriveGeneric #-}
+{-# LANGUAGE OverloadedStrings #-}
+
+module Wire
+  ( Bundle (..)
+  , BundleManifest (..)
+  , TreeSpec (..)
+  , NodeHashSpec (..)
+  , RuntimeSpec (..)
+  , BundleRoot (..)
+  , BundleExport (..)
+  , BundleMetadata
+  , ClosureMode (..)
+  , encodeBundle
+  , decodeBundle
+  , verifyBundle
+  , collectReachableNodes
+  , exportBundle
+  , exportNamedBundle
+  , importBundle
+  , defaultExportNames
+  ) where
+
+import ContentStore (getNodeMerkle, loadTree, putMerkleNode, storeTerm)
+import Research
+
+import Control.Exception (SomeException, evaluate, try)
+import Control.Monad (foldM, unless, when)
+import Crypto.Hash (Digest, SHA256, hash)
+import Data.Bits ((.|.), (.&.), shiftL, shiftR)
+import Data.ByteArray (convert)
+import Data.ByteString (ByteString)
+import Data.Foldable (traverse_)
+import Data.Map (Map)
+import Data.Text (Text, unpack)
+import Data.Text.Encoding (decodeUtf8, decodeUtf8', encodeUtf8)
+import Data.Word (Word16, Word32, Word64, Word8)
+import Database.SQLite.Simple (Connection)
+import GHC.Generics (Generic)
+
+import qualified Data.ByteString as BS
+import qualified Data.ByteString.Base16 as Base16
+import qualified Data.Map as Map
+import qualified Data.Set as Set
+import qualified Data.Text as T
+
+-- | Portable bundle major/minor version supported by this module.
+bundleMajorVersion :: Word16
+bundleMajorVersion = 1
+
+bundleMinorVersion :: Word16
+bundleMinorVersion = 0
+
+-- | Header magic for the portable executable-object container.
+bundleMagic :: ByteString
+bundleMagic = BS.pack [0x41, 0x52, 0x42, 0x4f, 0x52, 0x49, 0x43, 0x58] -- "ARBORICX"
+
+headerLength :: Int
+headerLength = 32
+
+sectionEntryLength :: Int
+sectionEntryLength = 60
+
+sectionManifest, sectionNodes :: Word32
+sectionManifest = 1
+sectionNodes = 2
+
+flagCritical :: Word16
+flagCritical = 0x0001
+
+compressionNone, digestSha256 :: Word16
+compressionNone = 0
+digestSha256 = 1
+
+-- ---------------------------------------------------------------------------
+-- Manifest binary constants
+-- ---------------------------------------------------------------------------
+
+-- | Magic prefix identifying the fixed-order manifest v1 format.
+manifestMagic :: ByteString
+manifestMagic = "ARBMNFST"
+
+-- | Manifest major version.
+manifestMajorVersion :: Word16
+manifestMajorVersion = 1
+
+-- | Manifest minor version.
+manifestMinorVersion :: Word16
+manifestMinorVersion = 0
+
+-- | Closure mode to byte.
+closureToByte :: ClosureMode -> Word8
+closureToByte = \case
+  ClosureComplete -> 0
+  ClosurePartial  -> 1
+
+closureFromByte :: Word8 -> Either String ClosureMode
+closureFromByte = \case
+  0 -> Right ClosureComplete
+  1 -> Right ClosurePartial
+  n -> Left $ "unsupported closure byte: " ++ show n
+
+-- | Metadata tag constants.
+tagPackage, tagVersion, tagDescription, tagLicense, tagCreatedBy :: Word16
+tagPackage    = 1
+tagVersion    = 2
+tagDescription = 3
+tagLicense    = 4
+tagCreatedBy  = 5
+
+-- ---------------------------------------------------------------------------
+-- Fixed-order manifest binary helpers
+-- ---------------------------------------------------------------------------
+
+-- | Encode a UTF-8 text string as: u32 length + UTF-8 bytes.
+encodeLengthPrefixedText :: Text -> ByteString
+encodeLengthPrefixedText t = encode32 (fromIntegral $ BS.length bs) <> bs
+  where bs = encodeUtf8 t
+
+-- | Decode a length-prefixed UTF-8 text string.
+-- Returns the decoded Text and the remaining ByteString.
+decodeLengthPrefixedText :: ByteString -> Either String (Text, ByteString)
+decodeLengthPrefixedText bs =
+  case decode32be "text_length" bs of
+    Left err -> Left $ "decodeLengthPrefixedText: " ++ err
+    Right (len, rest) -> do
+      let payloadLen = fromIntegral len
+      when (BS.length rest < payloadLen) $
+        Left "decodeLengthPrefixedText: string extends beyond input"
+      let (textBytes, after) = BS.splitAt payloadLen rest
+      case decodeUtf8' textBytes of
+        Right txt -> Right (txt, after)
+        Left _    -> Left "decodeLengthPrefixedText: invalid UTF-8"
+
+-- | Encode a metadata value as a TLV entry: u16 tag + u32 length + raw bytes.
+encodeMetadataTLV :: Word16 -> ByteString -> ByteString
+encodeMetadataTLV tag val = encode16 tag <> encode32 (fromIntegral $ BS.length val) <> val
+
+-- ---------------------------------------------------------------------------
+-- Fixed-order manifest encoders
+-- ---------------------------------------------------------------------------
+
+-- | Encode the entire manifest in fixed-order core + TLV tail layout.
+encodeManifest :: BundleManifest -> ByteString
+encodeManifest m =
+  manifestMagic
+    <> encode16 manifestMajorVersion
+    <> encode16 manifestMinorVersion
+    <> encodeLengthPrefixedText (manifestSchema m)
+    <> encodeLengthPrefixedText (manifestBundleType m)
+    <> encodeLengthPrefixedText (treeCalculus (manifestTree m))
+    <> encodeLengthPrefixedText (nodeHashAlgorithm (treeNodeHash (manifestTree m)))
+    <> encodeLengthPrefixedText (nodeHashDomain (treeNodeHash (manifestTree m)))
+    <> encodeLengthPrefixedText (treeNodePayload (manifestTree m))
+    <> encodeLengthPrefixedText (runtimeSemantics (manifestRuntime m))
+    <> encodeLengthPrefixedText (runtimeEvaluation (manifestRuntime m))
+    <> encodeLengthPrefixedText (runtimeAbi (manifestRuntime m))
+    <> encode32 (fromIntegral $ length (runtimeCapabilities (manifestRuntime m)))
+    <> encodeCapabilities (runtimeCapabilities (manifestRuntime m))
+    <> BS.pack [closureToByte (manifestClosure m)]
+    <> encode32 (fromIntegral $ length (manifestRoots m))
+    <> encodeRoots (manifestRoots m)
+    <> encode32 (fromIntegral $ length (manifestExports m))
+    <> encodeExports (manifestExports m)
+    <> encodeMetadataTLVs (manifestMetadata m)
+    <> encode32 0  -- zero extension fields
+
+encodeCapabilities :: [Text] -> ByteString
+encodeCapabilities caps = mconcat (map encodeLengthPrefixedText caps)
+
+encodeRoots :: [BundleRoot] -> ByteString
+encodeRoots = mconcat . map encodeRoot
+
+encodeRoot :: BundleRoot -> ByteString
+encodeRoot root =
+  merkleHashToRaw (rootHash root)
+    <> encodeLengthPrefixedText (rootRole root)
+
+encodeExports :: [BundleExport] -> ByteString
+encodeExports = mconcat . map encodeExport
+
+encodeExport :: BundleExport -> ByteString
+encodeExport exp =
+  encodeLengthPrefixedText (exportName exp)
+    <> merkleHashToRaw (exportRoot exp)
+    <> encodeLengthPrefixedText (exportKind exp)
+    <> encodeLengthPrefixedText (exportAbi exp)
+
+-- | Encode metadata as: u32 field count + TLV entries for present fields.
+-- Metadata TLV values are raw UTF-8 bytes; the TLV length already carries size.
+encodeMetadataTLVs :: BundleMetadata -> ByteString
+encodeMetadataTLVs m =
+  let entries = metadataTLVEntries m
+  in encode32 (fromIntegral $ length entries) <> encodeTLVs entries
+
+metadataTLVEntries :: BundleMetadata -> [(Word16, ByteString)]
+metadataTLVEntries m =
+  maybeEntry tagPackage (metadataPackage m)
+    ++ maybeEntry tagVersion (metadataVersion m)
+    ++ maybeEntry tagDescription (metadataDescription m)
+    ++ maybeEntry tagLicense (metadataLicense m)
+    ++ maybeEntry tagCreatedBy (metadataCreatedBy m)
+  where
+    maybeEntry _ Nothing = []
+    maybeEntry tag (Just value) = [(tag, encodeUtf8 value)]
+
+encodeTLVs :: [(Word16, ByteString)] -> ByteString
+encodeTLVs tlvs = mconcat (map (uncurry encodeMetadataTLV) tlvs)
+
+-- ---------------------------------------------------------------------------
+-- Fixed-order manifest decoders
+-- ---------------------------------------------------------------------------
+
+-- | Decode the manifest from fixed-order core + TLV tail bytes.
+-- All remaining bytes after the core fields are treated as the TLV tail.
+decodeManifest :: ByteString -> Either String BundleManifest
+decodeManifest bs = do
+  -- Header
+  when (BS.length bs < 8) $ Left "manifest too short for magic"
+  when (BS.take 8 bs /= manifestMagic) $ Left "invalid manifest magic"
+  let rest = BS.drop 8 bs
+  (major, rest') <- decode16be "major" rest
+  when (major /= manifestMajorVersion) $ Left $ "unsupported manifest major version: " ++ show major
+  (_minor, rest'') <- decode16be "minor" rest'
+
+  -- Core strings
+  (schema, rest''') <- decodeLengthPrefixedText rest''
+  (bundleType, rest'''') <- decodeLengthPrefixedText rest'''
+
+  -- Tree spec fields (flat)
+  (calc, rest1) <- decodeLengthPrefixedText rest''''
+  (alg, rest2) <- decodeLengthPrefixedText rest1
+  (domain, rest3) <- decodeLengthPrefixedText rest2
+  (payload, rest4) <- decodeLengthPrefixedText rest3
+
+  -- Runtime spec fields (flat)
+  (sem, restR1) <- decodeLengthPrefixedText rest4
+  (eval, restR2) <- decodeLengthPrefixedText restR1
+  (abi, restR3) <- decodeLengthPrefixedText restR2
+
+  (capCount, restR4) <- decode32be "capability_count" restR3
+  let capLen = fromIntegral capCount
+  (caps, restR5) <- decodeCapabilities capLen restR4
+
+  -- Closure
+  when (BS.length restR5 < 1) $ Left "manifest truncated: missing closure byte"
+  let (closureByte, restR6) = BS.splitAt 1 restR5
+  closure <- closureFromByte (head $ BS.unpack closureByte)
+
+  -- Roots
+  (rootCount, restR7) <- decode32be "root_count" restR6
+  let rootCountInt = fromIntegral rootCount
+  (roots, restR8) <- decodeRoots rootCountInt restR7
+
+  -- Exports
+  (exportCount, restR9) <- decode32be "export_count" restR8
+  let exportCountInt = fromIntegral exportCount
+  (exports, restR10) <- decodeExports exportCountInt restR9
+
+  -- TLV tail
+  (metadata, _ext) <- decodeMetadataAndExtensions restR10
+
+  pure BundleManifest
+    { manifestSchema = schema
+    , manifestBundleType = bundleType
+    , manifestTree = TreeSpec
+        { treeCalculus = calc
+        , treeNodeHash = NodeHashSpec
+            { nodeHashAlgorithm = alg
+            , nodeHashDomain = domain
+            }
+        , treeNodePayload = payload
+        }
+    , manifestRuntime = RuntimeSpec
+        { runtimeSemantics = sem
+        , runtimeEvaluation = eval
+        , runtimeAbi = abi
+        , runtimeCapabilities = caps
+        }
+    , manifestClosure = closure
+    , manifestRoots = roots
+    , manifestExports = exports
+    , manifestMetadata = metadata
+    }
+
+-- | Decode length-prefixed capability strings.
+decodeCapabilities :: Int -> ByteString -> Either String ([Text], ByteString)
+decodeCapabilities 0 bs = Right ([], bs)
+decodeCapabilities n bs = do
+  (txt, rest) <- decodeLengthPrefixedText bs
+  (restTxts, restFinal) <- decodeCapabilities (n - 1) rest
+  Right (txt : restTxts, restFinal)
+
+-- | Decode root entries.
+decodeRoots :: Int -> ByteString -> Either String ([BundleRoot], ByteString)
+decodeRoots 0 bs = Right ([], bs)
+decodeRoots n bs = do
+  when (BS.length bs < 32) $ Left "decodeRoots: truncated root hash"
+  let (hashBytes, rest) = BS.splitAt 32 bs
+  role <- decodeLengthPrefixedText rest
+  (restRoots, restFinal) <- decodeRoots (n - 1) (snd role)
+  Right (BundleRoot (rawToMerkleHash hashBytes) (fst role) : restRoots, restFinal)
+
+-- | Decode export entries.
+decodeExports :: Int -> ByteString -> Either String ([BundleExport], ByteString)
+decodeExports 0 bs = Right ([], bs)
+decodeExports n bs = do
+  name <- decodeLengthPrefixedText bs
+  when (BS.length (snd name) < 32) $ Left "decodeExports: truncated export root hash"
+  let (hashBytes, rest) = BS.splitAt 32 (snd name)
+  kind <- decodeLengthPrefixedText rest
+  abi <- decodeLengthPrefixedText (snd kind)
+  (restExports, restFinal) <- decodeExports (n - 1) (snd abi)
+  Right (BundleExport (fst name) (rawToMerkleHash hashBytes) (fst kind) (fst abi) : restExports, restFinal)
+
+-- | Decode TLV tail into metadata and extensions.
+-- Layout: u32 metadata-count, metadata TLVs, u32 extension-count, extension TLVs.
+-- For now, known metadata tags are decoded and extension TLVs are skipped.
+decodeMetadataAndExtensions :: ByteString -> Either String (BundleMetadata, ByteString)
+decodeMetadataAndExtensions bs = do
+  (metadataCount, rest1) <- decode32be "metadata_field_count" bs
+  (metadataTlvs, rest2) <- decodeTLVs (fromIntegral metadataCount) rest1
+  metadata <- decodeMetadataTLVs metadataTlvs
+  (extensionCount, rest3) <- decode32be "extension_field_count" rest2
+  (_extensionTlvs, rest4) <- decodeTLVs (fromIntegral extensionCount) rest3
+  unless (BS.null rest4) $ Left "trailing bytes after manifest TLV tail"
+  Right (metadata, rest4)
+
+-- | Decode a fixed number of TLV entries.
+decodeTLVs :: Int -> ByteString -> Either String ([TLVEntry], ByteString)
+decodeTLVs 0 bs = Right ([], bs)
+decodeTLVs n bs = do
+  (tag, rest1) <- decode16be "tlv_tag" bs
+  (len, rest2) <- decode32be "tlv_length" rest1
+  let payloadLen = fromIntegral len
+  when (BS.length rest2 < payloadLen) $ Left "TLV value extends beyond input"
+  let (value, after) = BS.splitAt payloadLen rest2
+  (restTlvs, restFinal) <- decodeTLVs (n - 1) after
+  Right ((tag, value) : restTlvs, restFinal)
+
+-- | Decode known metadata TLV entries into BundleMetadata.
+-- Unknown tags are ignored.
+decodeMetadataTLVs :: [(Word16, ByteString)] -> Either String BundleMetadata
+decodeMetadataTLVs tlvs = do
+  pkg <- decodeOptionalMetadataText tagPackage
+  ver <- decodeOptionalMetadataText tagVersion
+  desc <- decodeOptionalMetadataText tagDescription
+  lic <- decodeOptionalMetadataText tagLicense
+  by <- decodeOptionalMetadataText tagCreatedBy
+  pure BundleMetadata
+    { metadataPackage = pkg
+    , metadataVersion = ver
+    , metadataDescription = desc
+    , metadataLicense = lic
+    , metadataCreatedBy = by
+    }
+  where
+    lookupTag t = go t tlvs
+    go _ [] = Nothing
+    go t ((tag, val):rest)
+      | tag == t  = Just val
+      | otherwise = go t rest
+    decodeOptionalMetadataText tag =
+      case lookupTag tag of
+        Nothing -> Right Nothing
+        Just raw -> case decodeUtf8' raw of
+          Right txt -> Right (Just txt)
+          Left _ -> Left $ "metadata TLV has invalid UTF-8 for tag " ++ show tag
+
+type TLVEntry = (Word16, ByteString)
+
+-- ---------------------------------------------------------------------------
+-- Data types
+-- ---------------------------------------------------------------------------
+
+-- | Closure declaration.
+data ClosureMode = ClosureComplete | ClosurePartial
+  deriving (Show, Eq, Ord, Generic)
+
+-- | Hash specification (algorithm + domain strings).
+data NodeHashSpec = NodeHashSpec
+  { nodeHashAlgorithm :: Text
+  , nodeHashDomain :: Text
+  } deriving (Show, Eq, Ord, Generic)
+
+-- | Tree specification.
+data TreeSpec = TreeSpec
+  { treeCalculus :: Text
+  , treeNodeHash :: NodeHashSpec
+  , treeNodePayload :: Text
+  } deriving (Show, Eq, Ord, Generic)
+
+-- | Runtime specification.
+data RuntimeSpec = RuntimeSpec
+  { runtimeSemantics :: Text
+  , runtimeEvaluation :: Text
+  , runtimeAbi :: Text
+  , runtimeCapabilities :: [Text]
+  } deriving (Show, Eq, Ord, Generic)
+
+-- | A root hash reference.
+data BundleRoot = BundleRoot
+  { rootHash :: MerkleHash
+  , rootRole :: Text
+  } deriving (Show, Eq, Ord, Generic)
+
+-- | An export entry.
+data BundleExport = BundleExport
+  { exportName :: Text
+  , exportRoot :: MerkleHash
+  , exportKind :: Text
+  , exportAbi :: Text
+  } deriving (Show, Eq, Ord, Generic)
+
+-- | Optional package metadata.
+data BundleMetadata = BundleMetadata
+  { metadataPackage :: Maybe Text
+  , metadataVersion :: Maybe Text
+  , metadataDescription :: Maybe Text
+  , metadataLicense :: Maybe Text
+  , metadataCreatedBy :: Maybe Text
+  } deriving (Show, Eq, Ord, Generic)
+
+-- | The manifest: top-level bundle metadata.
+data BundleManifest = BundleManifest
+  { manifestSchema :: Text
+  , manifestBundleType :: Text
+  , manifestTree :: TreeSpec
+  , manifestRuntime :: RuntimeSpec
+  , manifestClosure :: ClosureMode
+  , manifestRoots :: [BundleRoot]
+  , manifestExports :: [BundleExport]
+  , manifestMetadata :: BundleMetadata
+  } deriving (Show, Eq, Generic)
+
+-- | Portable executable-object bundle.
+--
+-- Merkle node payloads remain the language-neutral executable core:
+--   Leaf = 0x00; Stem = 0x01 || child_hash; Fork = 0x02 || left_hash || right_hash.
+-- Names, exports, runtime metadata, and package metadata live in the manifest layer.
+data Bundle = Bundle
+  { bundleVersion :: Word16
+  , bundleRoots :: [MerkleHash]
+  , bundleNodes :: Map MerkleHash ByteString
+  , bundleManifest :: BundleManifest
+  , bundleManifestBytes :: ByteString
+  } deriving (Show, Eq)
+
+-- ---------------------------------------------------------------------------
+-- Bundle encoding
+-- ---------------------------------------------------------------------------
+
+-- | Encode a Bundle to portable Bundle v1 bytes.
+-- The manifest is serialized using the fixed-order core + TLV tail format.
+encodeBundle :: Bundle -> ByteString
+encodeBundle bundle =
+  let nodeSection = encodeNodeSection (bundleNodes bundle)
+      manifestBytes = if BS.null (bundleManifestBytes bundle)
+        then encodeManifest (bundleManifest bundle)
+        else bundleManifestBytes bundle
+      sectionCount = 2
+      dirOffset = fromIntegral headerLength
+      sectionDirLength = sectionCount * sectionEntryLength
+      manifestOffset = fromIntegral (headerLength + sectionDirLength)
+      nodesOffset = manifestOffset + fromIntegral (BS.length manifestBytes)
+      manifestEntry = encodeSectionEntry sectionManifest 1 flagCritical compressionNone
+        manifestOffset (fromIntegral $ BS.length manifestBytes) manifestBytes
+      nodesEntry = encodeSectionEntry sectionNodes 1 flagCritical compressionNone
+        nodesOffset (fromIntegral $ BS.length nodeSection) nodeSection
+      header = encodeHeader bundleMajorVersion bundleMinorVersion
+        (fromIntegral sectionCount) 0 dirOffset
+  in header <> manifestEntry <> nodesEntry <> manifestBytes <> nodeSection
+
+-- | Decode portable Bundle v1 bytes.
+decodeBundle :: ByteString -> Either String Bundle
+decodeBundle bs
+  | BS.take (BS.length bundleMagic) bs == bundleMagic = decodePortableBundle bs
+  | otherwise = Left "invalid magic"
+
+-- ---------------------------------------------------------------------------
+-- Portable container encoding / decoding
+-- ---------------------------------------------------------------------------
+
+data SectionEntry = SectionEntry
+  { seType :: Word32
+  , seVersion :: Word16
+  , seFlags :: Word16
+  , seCompression :: Word16
+  , seDigestAlgorithm :: Word16
+  , seOffset :: Word64
+  , seLength :: Word64
+  , seDigest :: ByteString
+  } deriving (Show, Eq)
+
+encodeHeader :: Word16 -> Word16 -> Word32 -> Word64 -> Word64 -> ByteString
+encodeHeader major minor sectionCount flags dirOffset =
+  bundleMagic
+    <> encode16 major
+    <> encode16 minor
+    <> encode32 sectionCount
+    <> encode64 flags
+    <> encode64 dirOffset
+
+encodeSectionEntry :: Word32 -> Word16 -> Word16 -> Word16 -> Word64 -> Word64 -> ByteString -> ByteString
+encodeSectionEntry sectionType sectionVersion sectionFlags compression offset lengthBytes sectionBytes =
+  encode32 sectionType
+    <> encode16 sectionVersion
+    <> encode16 sectionFlags
+    <> encode16 compression
+    <> encode16 digestSha256
+    <> encode64 offset
+    <> encode64 lengthBytes
+    <> sha256 sectionBytes
+
+decodePortableBundle :: ByteString -> Either String Bundle
+decodePortableBundle bs = do
+  (major, minor, sectionCount, _flags, dirOffset) <- decodePortableHeader bs
+  when (major /= bundleMajorVersion) $
+    Left $ "unsupported bundle major version: " ++ show major
+  let dirStart = fromIntegral dirOffset
+      dirBytes = fromIntegral sectionCount * sectionEntryLength
+  when (BS.length bs < dirStart + dirBytes) $
+    Left "bundle truncated in section directory"
+  let dirRaw = BS.take dirBytes $ BS.drop dirStart bs
+  entries <- decodeSectionEntries sectionCount dirRaw
+  traverse_ rejectUnknownCritical entries
+  manifestEntry <- requireSection sectionManifest entries
+  nodesEntry <- requireSection sectionNodes entries
+  manifestBytes <- readAndVerifySection bs manifestEntry
+  nodesBytes <- readAndVerifySection bs nodesEntry
+  manifest <- decodeManifest manifestBytes
+  nodes <- decodeNodeSection nodesBytes
+  let roots = map rootHash (manifestRoots manifest)
+  return Bundle
+    { bundleVersion = major * 1000 + minor
+    , bundleRoots = roots
+    , bundleNodes = nodes
+    , bundleManifest = manifest
+    , bundleManifestBytes = manifestBytes
+    }
+
+rejectUnknownCritical :: SectionEntry -> Either String ()
+rejectUnknownCritical entry =
+  let known = seType entry `elem` [sectionManifest, sectionNodes]
+      critical = seFlags entry .&. flagCritical /= 0
+  in when (critical && not known) $
+       Left $ "unknown critical section type: " ++ show (seType entry)
+
+requireSection :: Word32 -> [SectionEntry] -> Either String SectionEntry
+requireSection sectionType entries =
+  case filter ((== sectionType) . seType) entries of
+    [entry] -> Right entry
+    [] -> Left $ "missing required section type: " ++ show sectionType
+    _ -> Left $ "duplicate section type: " ++ show sectionType
+
+readAndVerifySection :: ByteString -> SectionEntry -> Either String ByteString
+readAndVerifySection bs entry = do
+  when (seCompression entry /= compressionNone) $
+    Left $ "unsupported compression codec in section " ++ show (seType entry)
+  when (seDigestAlgorithm entry /= digestSha256) $
+    Left $ "unsupported digest algorithm in section " ++ show (seType entry)
+  let offset = fromIntegral (seOffset entry)
+      len = fromIntegral (seLength entry)
+  when (offset < 0 || len < 0 || BS.length bs < offset + len) $
+    Left $ "section extends beyond bundle end: " ++ show (seType entry)
+  let sectionBytes = BS.take len $ BS.drop offset bs
+  when (sha256 sectionBytes /= seDigest entry) $
+    Left $ "section digest mismatch: " ++ show (seType entry)
+  Right sectionBytes
+
+decodePortableHeader :: ByteString -> Either String (Word16, Word16, Word32, Word64, Word64)
+decodePortableHeader bs
+  | BS.length bs < headerLength = Left "bundle too short for header"
+  | BS.take 8 bs /= bundleMagic = Left "invalid portable bundle magic"
+  | otherwise = do
+      (major, r1) <- decode16be "major_version" (BS.drop 8 bs)
+      (minor, r2) <- decode16be "minor_version" r1
+      (sectionCount, r3) <- decode32be "section_count" r2
+      (flags, r4) <- decode64be "flags" r3
+      (dirOffset, _) <- decode64be "directory_offset" r4
+      Right (major, minor, sectionCount, flags, dirOffset)
+
+decodeSectionEntries :: Word32 -> ByteString -> Either String [SectionEntry]
+decodeSectionEntries count bytes = reverse <$> go count bytes []
+  where
+    go 0 _ acc = Right acc
+    go n bs acc = do
+      when (BS.length bs < sectionEntryLength) $
+        Left "section directory truncated"
+      (sectionType, r1) <- decode32be "section_type" bs
+      (sectionVersion, r2) <- decode16be "section_version" r1
+      (sectionFlags, r3) <- decode16be "section_flags" r2
+      (compression, r4) <- decode16be "compression_codec" r3
+      (digAlg, r5) <- decode16be "digest_algorithm" r4
+      (offset, r6) <- decode64be "section_offset" r5
+      (len, r7) <- decode64be "section_length" r6
+      let (dig, rest) = BS.splitAt 32 r7
+      when (BS.length dig /= 32) $ Left "section digest truncated"
+      let entry = SectionEntry sectionType sectionVersion sectionFlags compression digAlg offset len dig
+      go (n - 1) rest (entry : acc)
+
+-- ---------------------------------------------------------------------------
+-- Manifest construction
+-- ---------------------------------------------------------------------------
+
+defaultManifest :: [(Text, MerkleHash)] -> BundleManifest
+defaultManifest namedRoots = BundleManifest
+  { manifestSchema = "arboricx.bundle.manifest.v1"
+  , manifestBundleType = "tree-calculus-executable-object"
+  , manifestTree = TreeSpec
+      { treeCalculus = "tree-calculus.v1"
+      , treeNodeHash = NodeHashSpec
+          { nodeHashAlgorithm = "sha256"
+          , nodeHashDomain = "arboricx.merkle.node.v1"
+          }
+      , treeNodePayload = "arboricx.merkle.payload.v1"
+      }
+  , manifestRuntime = RuntimeSpec
+      { runtimeSemantics = "tree-calculus.v1"
+      , runtimeEvaluation = "normal-order"
+      , runtimeAbi = "arboricx.abi.tree.v1"
+      , runtimeCapabilities = []
+      }
+  , manifestClosure = ClosureComplete
+  , manifestRoots = zipWith mkRoot [0 :: Int ..] (map snd namedRoots)
+  , manifestExports = map mkExport namedRoots
+  , manifestMetadata = BundleMetadata
+      { metadataPackage   = Nothing
+      , metadataVersion   = Nothing
+      , metadataDescription = Nothing
+      , metadataLicense   = Nothing
+      , metadataCreatedBy = Just "arboricx"
+      }
+  }
+  where
+    mkRoot 0 h = BundleRoot h "default"
+    mkRoot _ h = BundleRoot h "root"
+    mkExport (name, h) = BundleExport
+      { exportName = name
+      , exportRoot = h
+      , exportKind = "term"
+      , exportAbi = "arboricx.abi.tree.v1"
+      }
+
+-- ---------------------------------------------------------------------------
+-- Node section encoding / decoding
+-- ---------------------------------------------------------------------------
+
+encodeNodeSection :: Map MerkleHash ByteString -> ByteString
+encodeNodeSection nodes =
+  encode64 (fromIntegral $ Map.size nodes)
+    <> mconcat (map nodeEntryToBinary $ Map.toAscList nodes)
+
+-- | Encode a single (hash, canonical-payload) node entry.
+nodeEntryToBinary :: (MerkleHash, ByteString) -> ByteString
+nodeEntryToBinary (h, payload) =
+  merkleHashToRaw h
+    <> encode32 (fromIntegral $ BS.length payload)
+    <> payload
+
+decodeNodeSection :: ByteString -> Either String (Map MerkleHash ByteString)
+decodeNodeSection bs = do
+  (nodeCount, rest) <- decode64be "node_count" bs
+  decodeNodeEntries nodeCount rest
+
+-- | Decode a sequence of node entries.
+decodeNodeEntries :: Word64 -> ByteString -> Either String (Map MerkleHash ByteString)
+decodeNodeEntries count bs = go count bs Map.empty
+  where
+    go 0 rest acc
+      | BS.null rest = Right acc
+      | otherwise = Left "trailing bytes after node section"
+    go n bytes acc
+      | BS.length bytes < 36 =
+          Left "not enough bytes for node entry header (hash + length)"
+      | otherwise = do
+          let (hashBytes, rest) = BS.splitAt 32 bytes
+          (plen, rest') <- decode32be "payload_len" rest
+          let payloadLen = fromIntegral plen
+          if BS.length rest' < payloadLen
+            then Left "payload extends beyond node section end"
+            else do
+              let (payload, after) = BS.splitAt payloadLen rest'
+                  h = rawToMerkleHash hashBytes
+              when (Map.member h acc) $
+                Left $ "duplicate node entry: " ++ unpack h
+              go (n - 1) after (Map.insert h payload acc)
+
+-- ---------------------------------------------------------------------------
+-- Bundle verification
+-- ---------------------------------------------------------------------------
+
+verifyBundle :: Bundle -> Either String ()
+verifyBundle bundle
+  | bundleVersion bundle < 1 = Left $ "unsupported bundle version: " ++ show (bundleVersion bundle)
+  | Map.null (bundleNodes bundle) = Left "bundle has no nodes"
+verifyBundle bundle = do
+  verifyManifest (bundleManifest bundle)
+  let nodeMap = bundleNodes bundle
+      rootSet = Set.fromList (bundleRoots bundle)
+      manifestRootSet = Set.fromList (map rootHash $ manifestRoots $ bundleManifest bundle)
+      exportRoots = map exportRoot $ manifestExports $ bundleManifest bundle
+  unless (rootSet == manifestRootSet) $
+    Left "bundle root list does not match manifest roots"
+  traverse_ (requirePresent "root hash missing from bundle") (bundleRoots bundle)
+  traverse_ (requirePresent "export root hash missing from bundle") exportRoots
+  decoded <- traverse verifyNodePayload (Map.toList nodeMap)
+  traverse_ (verifyChildrenPresent nodeMap) decoded
+  verifyCompleteClosure nodeMap (bundleRoots bundle)
+  where
+    requirePresent label h =
+      unless (Map.member h (bundleNodes bundle)) $
+        Left $ label ++ ": " ++ unpack h
+
+verifyManifest :: BundleManifest -> Either String ()
+verifyManifest manifest = do
+  when (manifestSchema manifest /= "arboricx.bundle.manifest.v1") $
+    Left $ "unsupported manifest schema: " ++ unpack (manifestSchema manifest)
+  when (manifestBundleType manifest /= "tree-calculus-executable-object") $
+    Left $ "unsupported bundle type: " ++ unpack (manifestBundleType manifest)
+  let treeSpec = manifestTree manifest
+      hashSpec = treeNodeHash treeSpec
+      runtimeSpec = manifestRuntime manifest
+  when (treeCalculus treeSpec /= "tree-calculus.v1") $
+    Left $ "unsupported calculus: " ++ unpack (treeCalculus treeSpec)
+  when (nodeHashAlgorithm hashSpec /= "sha256") $
+    Left $ "unsupported node hash algorithm: " ++ unpack (nodeHashAlgorithm hashSpec)
+  when (nodeHashDomain hashSpec /= "arboricx.merkle.node.v1") $
+    Left $ "unsupported node hash domain: " ++ unpack (nodeHashDomain hashSpec)
+  when (treeNodePayload treeSpec /= "arboricx.merkle.payload.v1") $
+    Left $ "unsupported node payload: " ++ unpack (treeNodePayload treeSpec)
+  when (runtimeSemantics runtimeSpec /= "tree-calculus.v1") $
+    Left $ "unsupported runtime semantics: " ++ unpack (runtimeSemantics runtimeSpec)
+  when (runtimeAbi runtimeSpec /= "arboricx.abi.tree.v1") $
+    Left $ "unsupported runtime ABI: " ++ unpack (runtimeAbi runtimeSpec)
+  when (not (null (runtimeCapabilities runtimeSpec))) $
+    Left "unsupported runtime capabilities"
+  when (manifestClosure manifest /= ClosureComplete) $
+    Left "bundle v1 requires closure = complete"
+  when (null $ manifestRoots manifest) $
+    Left "manifest has no roots"
+  when (null $ manifestExports manifest) $
+    Left "manifest has no exports"
+  traverse_ verifyExport (manifestExports manifest)
+  where
+    verifyExport exported = do
+      when (T.null $ exportName exported) $
+        Left "manifest export has empty name"
+      when (T.null $ exportRoot exported) $
+        Left "manifest export has empty root"
+
+verifyNodePayload :: (MerkleHash, ByteString) -> Either String (MerkleHash, Node)
+verifyNodePayload (h, payload) = do
+  node <- safeDeserializeNode payload
+  let actual = nodeHash node
+  unless (actual == h) $
+    Left $ "node hash mismatch for " ++ unpack h ++ "; payload hashes to " ++ unpack actual
+  Right (h, node)
+
+verifyChildrenPresent :: Map MerkleHash ByteString -> (MerkleHash, Node) -> Either String ()
+verifyChildrenPresent nodeMap (h, node) =
+  case node of
+    NLeaf -> Right ()
+    NStem child -> requireChild h child
+    NFork left right -> requireChild h left >> requireChild h right
+  where
+    requireChild parent child =
+      unless (Map.member child nodeMap) $
+        Left $ "missing child node referenced by " ++ unpack parent ++ ": " ++ unpack child
+
+verifyCompleteClosure :: Map MerkleHash ByteString -> [MerkleHash] -> Either String ()
+verifyCompleteClosure nodeMap roots = do
+  _ <- foldM visit Set.empty roots
+  Right ()
+  where
+    visit seen h
+      | Set.member h seen = Right seen
+      | otherwise = do
+          payload <- case Map.lookup h nodeMap of
+            Nothing -> Left $ "closure missing node: " ++ unpack h
+            Just p -> Right p
+          node <- safeDeserializeNode payload
+          let seen' = Set.insert h seen
+          case node of
+            NLeaf -> Right seen'
+            NStem child -> visit seen' child
+            NFork left right -> visit seen' left >>= \seenL -> visit seenL right
+
+safeDeserializeNode :: ByteString -> Either String Node
+safeDeserializeNode payload =
+  case BS.uncons payload of
+    Just (0x00, rest)
+      | BS.null rest -> Right NLeaf
+      | otherwise -> Left "invalid leaf payload length"
+    Just (0x01, rest)
+      | BS.length rest == 32 -> Right $ NStem (rawToMerkleHash rest)
+      | otherwise -> Left "invalid stem payload length"
+    Just (0x02, rest)
+      | BS.length rest == 64 ->
+          let (left, right) = BS.splitAt 32 rest
+          in Right $ NFork (rawToMerkleHash left) (rawToMerkleHash right)
+      | otherwise -> Left "invalid fork payload length"
+    _ -> Left "invalid merkle node payload"
+
+-- ---------------------------------------------------------------------------
+-- Reachability traversal
+-- ---------------------------------------------------------------------------
+
+collectReachableNodes :: Connection -> MerkleHash -> IO [(MerkleHash, ByteString)]
+collectReachableNodes conn root = do
+  let go seen current = do
+        case Map.lookup current seen of
+          Just _ -> return seen
+          Nothing -> do
+            maybeNode <- getNodeMerkle conn current
+            case maybeNode of
+              Nothing -> error $ "exportBundle: missing Merkle node: " ++ unpack current
+              Just node -> do
+                let payload = serializeNode node
+                    seen' = Map.insert current payload seen
+                case node of
+                  NLeaf -> return seen'
+                  NStem childHash -> go seen' childHash
+                  NFork lHash rHash -> go seen' lHash >>= \seenL -> go seenL rHash
+  seen <- go Map.empty root
+  return $ Map.toAscList seen
+
+-- ---------------------------------------------------------------------------
+-- High-level export / import
+-- ---------------------------------------------------------------------------
+
+exportBundle :: Connection -> [MerkleHash] -> IO ByteString
+exportBundle conn hashes = exportNamedBundle conn (zip (defaultExportNames $ length hashes) hashes)
+
+exportNamedBundle :: Connection -> [(Text, MerkleHash)] -> IO ByteString
+exportNamedBundle conn namedHashes = do
+  let hashes = map snd namedHashes
+  entries <- concat <$> mapM (collectReachableNodes conn) hashes
+  let nodeMap = Map.fromList entries
+      manifest = defaultManifest namedHashes
+      manifestBytes = encodeManifest manifest
+      bundle = Bundle
+        { bundleVersion = bundleMajorVersion * 1000 + bundleMinorVersion
+        , bundleRoots = hashes
+        , bundleNodes = nodeMap
+        , bundleManifest = manifest
+        , bundleManifestBytes = manifestBytes
+        }
+  return $ encodeBundle bundle
+
+importBundle :: Connection -> ByteString -> IO [MerkleHash]
+importBundle conn bs = case decodeBundle bs of
+  Left err -> error $ "Wire.importBundle: " ++ err
+  Right bundle -> case verifyBundle bundle of
+    Left err -> error $ "Wire.importBundle verify: " ++ err
+    Right () -> do
+      traverse_ (\payload -> do
+        node <- deserializeForImport payload
+        putMerkleNode conn node
+        )
+        (Map.elems $ bundleNodes bundle)
+      registerBundleExports conn bundle
+      return $ bundleRoots bundle
+
+registerBundleExports :: Connection -> Bundle -> IO ()
+registerBundleExports conn bundle =
+  traverse_ registerExport (manifestExports $ bundleManifest bundle)
+  where
+    registerExport exported = do
+      maybeTree <- loadTree conn (exportRoot exported)
+      case maybeTree of
+        Nothing -> error $ "Wire.importBundle: export root missing after node import: " ++ unpack (exportRoot exported)
+        Just tree -> do
+          _ <- storeTerm conn [unpack $ exportName exported] tree
+          return ()
+
+-- ---------------------------------------------------------------------------
+-- Primitive binary helpers
+-- ---------------------------------------------------------------------------
+
+encode16 :: Word16 -> ByteString
+encode16 w = BS.pack
+  [ fromIntegral (shiftR w 8)
+  , fromIntegral w
+  ]
+
+encode32 :: Word32 -> ByteString
+encode32 w = BS.pack
+  [ fromIntegral (shiftR w 24)
+  , fromIntegral (shiftR w 16)
+  , fromIntegral (shiftR w 8)
+  , fromIntegral w
+  ]
+
+encode64 :: Word64 -> ByteString
+encode64 w = BS.pack
+  [ fromIntegral (shiftR w 56)
+  , fromIntegral (shiftR w 48)
+  , fromIntegral (shiftR w 40)
+  , fromIntegral (shiftR w 32)
+  , fromIntegral (shiftR w 24)
+  , fromIntegral (shiftR w 16)
+  , fromIntegral (shiftR w 8)
+  , fromIntegral w
+  ]
+
+decode16be :: String -> ByteString -> Either String (Word16, ByteString)
+decode16be label bs
+  | BS.length bs < 2 = Left (label ++ ": not enough bytes for u16")
+  | otherwise =
+      let b0 = fromIntegral (BS.index bs 0) :: Word16
+          b1 = fromIntegral (BS.index bs 1) :: Word16
+      in Right ((b0 `shiftL` 8) .|. b1, BS.drop 2 bs)
+
+-- | Decode a big-endian u32 from the head of a ByteString.
+decode32be :: String -> ByteString -> Either String (Word32, ByteString)
+decode32be label bs
+  | BS.length bs < 4 = Left (label ++ ": not enough bytes for u32")
+  | otherwise =
+      let b0 = fromIntegral (BS.index bs 0) :: Word32
+          b1 = fromIntegral (BS.index bs 1) :: Word32
+          b2 = fromIntegral (BS.index bs 2) :: Word32
+          b3 = fromIntegral (BS.index bs 3) :: Word32
+          val = (b0 `shiftL` 24) .|. (b1 `shiftL` 16)
+                .|. (b2 `shiftL` 8) .|. b3
+      in Right (val, BS.drop 4 bs)
+
+decode64be :: String -> ByteString -> Either String (Word64, ByteString)
+decode64be label bs
+  | BS.length bs < 8 = Left (label ++ ": not enough bytes for u64")
+  | otherwise =
+      let byte i = fromIntegral (BS.index bs i) :: Word64
+          val = (byte 0 `shiftL` 56) .|. (byte 1 `shiftL` 48)
+                .|. (byte 2 `shiftL` 40) .|. (byte 3 `shiftL` 32)
+                .|. (byte 4 `shiftL` 24) .|. (byte 5 `shiftL` 16)
+                .|. (byte 6 `shiftL` 8) .|. byte 7
+      in Right (val, BS.drop 8 bs)
+
+-- ---------------------------------------------------------------------------
+-- Hash conversion
+-- ---------------------------------------------------------------------------
+
+-- | Convert a hex MerkleHash to its raw 32-byte representation.
+merkleHashToRaw :: MerkleHash -> ByteString
+merkleHashToRaw h =
+  case Base16.decode (encodeUtf8 h) of
+    Left _ -> error $ "Wire.merkleHashToRaw: invalid hex: " ++ show h
+    Right bs
+      | BS.length bs == 32 -> bs
+      | otherwise -> error $ "Wire.merkleHashToRaw: expected 32 bytes: " ++ show h
+
+-- | Convert raw 32 bytes back to a hex MerkleHash.
+rawToMerkleHash :: ByteString -> MerkleHash
+rawToMerkleHash bs = decodeUtf8 (Base16.encode bs)
+
+sha256 :: ByteString -> ByteString
+sha256 bytes = convert ((hash bytes) :: Digest SHA256)
+
+
+
+defaultExportNames :: Int -> [Text]
+defaultExportNames n =
+  case n of
+    0 -> []
+    1 -> ["root"]
+    _ -> ["root" <> T.pack (show i) | i <- [0 :: Int .. n - 1]]
+
+deserializeForImport :: ByteString -> IO Node
+deserializeForImport payload = do
+  result <- try (evaluate $ deserializeNode payload) :: IO (Either SomeException Node)
+  case result of
+    Left err -> error $ "Wire.importBundle: invalid merkle node payload: " ++ show err
+    Right node -> return node

test/comments-1.tri

@@ -1,9 +1,9 @@
 -- This is a tricu comment!
 -- t (t t) (t (t t t))
 -- t (t t t) (t t)
--- x = (\a : a)
+-- x = (a : a)
 main = t (t t) t -- Fork (Stem Leaf) Leaf
 -- t t
 -- x
--- x = (\a : a)
+-- x = (a : a)
 -- t

test/lambda-A.tri

@@ -1 +1 @@
-main = (\x : x) t
+main = (x : x) t

test/map.tri

@@ -1,2 +1,2 @@
-x = map (\i : append "Successfully concatenated " i) [("two strings!")]
+x = map (i : append "Successfully concatenated " i) [("two strings!")]
 main = equal? x [("Successfully concatenated two strings!")]

test/size.tri

@@ -1,21 +1,21 @@
-compose = \f g x : f (g x)
+compose = f g x : f (g x)
 
-succ = y (\self :
+succ = y (self :
   triage
     1
     t
     (triage
       (t (t t))
-      (\_ tail : t t (self tail))
+      (_ tail : t t (self tail))
       t))
 
-size = (\x :
-  (y (\self x :
+size = (x :
+  (y (self x :
     compose succ
       (triage
-        (\x : x)
+        (x : x)
         self
-        (\x y : compose (self x) (self y))
+        (x y : compose (self x) (self y))
         x)) x 0))
 
 size size

test/string.tri

@@ -1 +1 @@
-head (map (\i : append "String " i) [("test!")])
+head (map (i : append "String " i) [("test!")])

test/vars-B.tri

@@ -1 +1 @@
-y = \x : x
+y = x : x

tricu.cabal

@@ -1,8 +1,8 @@
 cabal-version: 1.12
 
 name:           tricu
-version:        0.16.0
-description:    A micro-language for exploring Tree Calculus
+version:        1.1.0
+description:    A language for exploring Tree Calculus
 author:         James Eversole
 maintainer:     james@eversole.co
 copyright:      James Eversole
@@ -15,31 +15,66 @@ extra-source-files:
 executable tricu
   main-is: Main.hs
   hs-source-dirs:
-      src
+    src
   default-extensions:
-      DeriveDataTypeable
-      LambdaCase
-      MultiWayIf
-      OverloadedStrings
-  ghc-options: -threaded -rtsopts -with-rtsopts=-N -optl-pthread -fPIC
+    DeriveDataTypeable
+    LambdaCase
+    MultiWayIf
+    OverloadedStrings
+    ScopedTypeVariables
+  ghc-options: 
+    -Wall
+    -Wcompat
+    -Wunused-imports
+    -Wunused-top-binds
+    -Wunused-local-binds
+    -Wunused-matches
+    -Wredundant-constraints
+    -threaded 
+    -rtsopts 
+    -with-rtsopts=-N 
+    -optl-pthread 
+    -fPIC
   build-depends:
     base >=4.7
+    , ansi-terminal
+    , base16-bytestring
+    , base64-bytestring
+    , bytestring
     , cmdargs
     , containers
+    , cryptonite
+    , directory
     , exceptions
     , filepath
+    , fsnotify
     , haskeline
+    , http-types
     , megaparsec
+    , memory
     , mtl
+    , servant
+    , sqlite-simple
+    , stm
+    , tasty
+    , tasty-hunit
     , text
+    , time
     , transformers
+    , wai
+    , warp
+    , zlib
   other-modules:
+    ContentStore
     Eval
     FileEval
     Lexer
     Parser
+    Paths_tricu
     REPL
     Research
+    Server
+    Wire
   default-language: Haskell2010
 
 test-suite tricu-tests
@@ -51,25 +86,45 @@ test-suite tricu-tests
       LambdaCase
       MultiWayIf
       OverloadedStrings
+      ScopedTypeVariables
   build-depends:       
-    base
+    base >=4.7
+    , ansi-terminal
+    , base16-bytestring
+    , base64-bytestring
+    , bytestring
     , cmdargs
     , containers
+    , cryptonite
+    , directory
     , exceptions
     , filepath
+    , fsnotify
     , haskeline
+    , http-types
     , megaparsec
+    , memory
     , mtl
+    , servant
+    , sqlite-simple
+    , stm
     , tasty
     , tasty-hunit
-    , tasty-quickcheck
     , text
+    , time
     , transformers
+    , wai
+    , warp
+    , zlib
   default-language:    Haskell2010
   other-modules:
+    ContentStore
     Eval
     FileEval
     Lexer
     Parser
+    Paths_tricu
     REPL
     Research
+    Server
+    Wire