gitdup

Duplicate your current project directory, reset tracked git changes, and optionally checkout a branch or PR — while keeping local config like .env.

Great for spinning up parallel workspaces for coding agents such as Codex CLI, so they can branch off a clean copy without losing environment files.

Install

Install globally from npm:

npm i -g gitdup

Or from source (if working locally):

# inside the repo
npm i -g .
# or
npm link

Usage

# Duplicate to a sibling folder (<cwd>-dup or -dup-N)
gitdup

# Specify destination (must not exist or must be empty)
gitdup ../my-project-dup

# Checkout a branch in the duplicate
gitdup -b feature/some-branch

# Fetch and checkout a GitHub PR (default remote: origin)
gitdup -p 123
gitdup -p 123 -r upstream

# Also remove untracked files (keeps ignored like .env)
gitdup --clean

# Verbose git output
gitdup -v

# Node projects: skip copying node_modules and auto-install deps
gitdup

# Disable install step if desired
gitdup --no-install

Behavior:

• Copies the entire directory (including .git and dotfiles) to preserve local config like .env.
• Resets tracked changes with git reset --hard. Untracked files are preserved unless --clean is passed.
• PR checkout uses GitHub-style refspecs (pull/<n>/head).
• If a destination is provided, it must not exist or must be an empty directory.
• Node optimization: If a package.json is present, node_modules folders are not copied. After copying, it auto-detects your package manager (npm, pnpm, yarn, bun) and runs install in the duplicate. Use --no-install to skip.

Requirements:

• Node.js >= 18
• Git installed and available on PATH
• Optional: npm/pnpm/yarn/bun installed if you want auto-install for Node projects

Development

Setup:

npm install

Build TypeScript → dist/:

npm run build

Run the CLI (built):

npm start
# or
node dist/cli.js

Link globally for testing:

npm link
gitdup

Scripts:

• build: Compile TypeScript to dist/.
• build:watch: Rebuild on changes.
• start: Run the built CLI.
• test: Run unit tests once (no watch).
• test:watch: Run unit tests in watch mode.
• lint: Lint with ESLint (auto-fix).
• lint:check: Lint without fixing.
• format: Auto-format with Prettier.
• check: Run Prettier check + ESLint (used on pre-push/publish).
• Pre-push: Husky runs npm run check and npm test before pushing.

Linting notes:

• Unused imports are auto-removed via eslint-plugin-unused-imports when running with --fix (used in npm run lint).
• For intentionally unused variables or parameters, prefix them with _ (config ignores ^_).

Publishing (manual):

# build runs via the prepare script during publish
npm publish

Project structure:

• src/cli.ts: CLI entry (compiled to dist/cli.js).
• src/index.ts: Implementation (copy + git operations).
• dist/: Compiled JS and type declarations.
• test/: Vitest unit tests.
• tsconfig.json: TS compiler config.
• .eslintrc.cjs: ESLint config.
• .prettierrc.json: Prettier config.