{
  lib,
  stdenv,
  fetchurl,
  nodejs,
  makeWrapper,
  patchelf,
  glibc,
}:

let
  version = "0.0.85";

  freebuffSrc = fetchurl {
    url = "https://registry.npmjs.org/freebuff/-/freebuff-${version}.tgz";
    hash = "sha256-1x593yLMkoFIO5O+k5NKeEpi729VhINQlW1xFbYGnXM=";
  };

  pkgTar = fetchurl {
    url = "https://registry.npmjs.org/tar/-/tar-7.5.15.tgz";
    hash = "sha256-hl60jJtM1W2THQyGZj8G72GEG8QvVrHvNnr7EU1liBw=";
  };

  pkgFsMinipass = fetchurl {
    url = "https://registry.npmjs.org/@isaacs/fs-minipass/-/fs-minipass-4.0.1.tgz";
    hash = "sha256-esKG48zMHqiYDnniA53va7l9MYLheVHNkJTwQA7ZgjY=";
  };

  pkgChownr = fetchurl {
    url = "https://registry.npmjs.org/chownr/-/chownr-3.0.0.tgz";
    hash = "sha256-TCT12qYwFCJS2oneZV998JDqR5RQqIJYl3UdeDIbE2A=";
  };

  pkgMinipass = fetchurl {
    url = "https://registry.npmjs.org/minipass/-/minipass-7.1.3.tgz";
    hash = "sha256-UqxhvnQ3VeP9yY5WAIbQ1KHix/02Qzh3kts44yLSfRI=";
  };

  pkgMinizlib = fetchurl {
    url = "https://registry.npmjs.org/minizlib/-/minizlib-3.1.0.tgz";
    hash = "sha256-mb8uKWGBct1x8GVHN0kMaPcbx+I3nUc+OPn+8tvs4uM=";
  };

  pkgYallist = fetchurl {
    url = "https://registry.npmjs.org/yallist/-/yallist-5.0.0.tgz";
    hash = "sha256-fJ1D26t8qzsxM7Dmpa8UAUSCKFMWs57J9QjvrdnrzpU=";
  };

  # Pre-built binary release from codebuff.com
  binarySrc = fetchurl {
    url = "https://codebuff.com/api/releases/download/${version}/freebuff-linux-x64.tar.gz";
    hash = "sha256-WRTEXqKDww4ZPAnDLAAkAd0jxl+z6+dRbcQORmN7QfM=";
  };

in

stdenv.mkDerivation rec {
  pname = "freebuff";
  version = "0.0.85";

  src = freebuffSrc;

  nativeBuildInputs = [ makeWrapper patchelf ];

  dontStrip = true;
  dontPatchelf = true;

  installPhase = ''
    runHook preInstall

    # Extract and patch the pre-built binary for NixOS compatibility
    mkdir -p "$out/bin" /tmp/fb-engine
    tar xzf "${binarySrc}" -C /tmp/fb-engine --strip-components=0
    cp /tmp/fb-engine/freebuff "$out/bin/freebuff-engine"
    chmod 755 "$out/bin/freebuff-engine"

    # Patch ELF interpreter and rpath for glibc on NixOS
    patchelf \
      --set-interpreter "${glibc}/lib/ld-linux-x86-64.so.2" \
      --set-rpath "${glibc}/lib:" \
      "$out/bin/freebuff-engine"

    # Copy tree-sitter.wasm next to the engine binary
    if [ -f /tmp/fb-engine/tree-sitter.wasm ]; then
      cp /tmp/fb-engine/tree-sitter.wasm "$out/bin/"
    fi

    rm -rf /tmp/fb-engine

    # Set up JS launcher and npm dependencies
    mkdir -p "$out/lib/node_modules/freebuff"
    cp -r * "$out/lib/node_modules/freebuff/"

    # Extract npm dependencies from pre-fetched tarballs
    extractNpmPkg() {
      local src="$1" target="$2"
      mkdir -p "$target"
      tar xzf "$src" -C "$target" --strip-components=1
    }

    extractNpmPkg "${pkgTar}" "$out/lib/node_modules/tar"
    extractNpmPkg "${pkgChownr}" "$out/lib/node_modules/chownr"
    extractNpmPkg "${pkgMinipass}" "$out/lib/node_modules/minipass"
    extractNpmPkg "${pkgMinizlib}" "$out/lib/node_modules/minizlib"
    extractNpmPkg "${pkgYallist}" "$out/lib/node_modules/yallist"
    mkdir -p "$out/lib/node_modules/@isaacs"
    extractNpmPkg "${pkgFsMinipass}" "$out/lib/node_modules/@isaacs/fs-minipass"

    # Create wrapper launcher that uses the pre-patched binary instead of downloading
    cat > "$out/lib/node_modules/freebuff/wrapper-launcher.js" << WRAPPER_EOF
#!/usr/bin/env node
const { spawn } = require('child_process');
const fs = require('fs');
const path = require('path');

// Use the Nix-store patched binary directly
const enginePath = process.env.FREEBUFF_ENGINE || '${placeholder "out"}/bin/freebuff-engine';

// Metadata path for version tracking
const configDir = path.join(process.env.HOME || '/', '.config', 'manicode');
const metadataPath = path.join(configDir, 'freebuff-metadata.json');

function resetTerminal() {
  try {
    if (process.stdin.isTTY && process.stdin.setRawMode) {
      process.stdin.setRawMode(false);
    }
  } catch {}
  try {
    const seqs = '\\x1b[?1049l\\x1b[?1000l\\x1b[?1002l\\x1b[?1003l\\x1b[?1006l\\x1b[?2004l\\x1b[?25h';
    if (process.stdout.isTTY) process.stdout.write(seqs);
  } catch {}
}

async function main() {
  // Copy patched binary to user config dir so the engine finds tree-sitter.wasm there too
  fs.mkdirSync(configDir, { recursive: true });
  const targetBinary = path.join(configDir, 'freebuff');
  const targetWasm = path.join(configDir, 'tree-sitter.wasm');

  // Install patched binary if not present or version mismatch
  let needsInstall = !fs.existsSync(targetBinary);
  if (!needsInstall) {
    try {
      const meta = JSON.parse(fs.readFileSync(metadataPath, 'utf8'));
      needsInstall = (meta.version !== '${version}');
    } catch {}
  }

  if (needsInstall) {
    try { fs.unlinkSync(targetBinary); } catch {}
    fs.copyFileSync(enginePath, targetBinary);
    fs.chmodSync(targetBinary, 0o755);
    fs.writeFileSync(metadataPath, JSON.stringify({ version: '${version}' }, null, 2));

    // Copy tree-sitter.wasm if available
    const wasmSrc = '${placeholder "out"}/bin/tree-sitter.wasm';
    if (fs.existsSync(wasmSrc)) {
      try { fs.copyFileSync(wasmSrc, targetWasm); } catch {}
    }
  }

  const child = spawn(targetBinary, process.argv.slice(2), {
    stdio: 'inherit',
    env: { ...process.env },
  });

  child.on('exit', (code, signal) => {
    resetTerminal();
    process.exit(signal ? 1 : (code || 0));
  });

  child.on('error', (err) => {
    console.error('Failed to start freebuff:', err.message);
    process.exit(1);
  });
}

main().catch((error) => {
  console.error('Unexpected error:', error.message);
  process.exit(1);
});
WRAPPER_EOF

    # Create the main binary wrapper
    makeWrapper "${nodejs}/bin/node" "$out/bin/freebuff" \
      --set NODE_PATH "$out/lib/node_modules" \
      --add-flags "$out/lib/node_modules/freebuff/wrapper-launcher.js"

    runHook postInstall
  '';

  doCheck = false;

  passthru = {
    category = "AI Coding Agents";
    updateScript = [
      "nix-update"
      "--flake"
      ".#freebuff"
    ];
  };

  meta = with lib; {
    description = "The world's strongest free coding agent";
    homepage = "https://codebuff.com";
    license = licenses.mit;
    mainProgram = "freebuff";
    platforms = platforms.linux;
  };
}