{
  description = "tricu";

  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs";
    flake-utils.url = "github:numtide/flake-utils";
  };

  outputs = { self, nixpkgs, flake-utils }:
    flake-utils.lib.eachDefaultSystem (system:
      let
        pkgs = nixpkgs.legacyPackages.${system};
        packageName = "tricu";
        containerPackageName = "${packageName}-container";

        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
        ]);

        # ------------------------------------------------------------------
        # 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/
          '';
        };

        # Separate test target — not included in `nix flake check`
        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

            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" > $out/result
          '';
        };
      in {
        packages.${packageName} = tricuPackage;
        packages.default = tricuPackage;
        packages.tricu-zig = tricuZig;
        packages.tricu-zig-tests = tricuZigTests;

        checks.${packageName} = tricuPackageTests;
        checks.default = tricuPackageTests;

        devShells.default = pkgs.mkShell {
          buildInputs = with pkgs; [
            haskellPackages.cabal-install
            haskellPackages.ghc-events
            haskellPackages.ghcid
            customGHC
            upx
            zig
            gcc
            python3
          ];

          inputsFrom = [
            tricuPackage
            tricuZig
          ];
        };

        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 = ''
            '';
          };
        };
      });
}