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name: build-a-project description: Create or update a Makefile with dev and build targets that run the repo's actual development and build commands. Use when asked to standardize run/build commands or add Makefile targets.

Build and Run Makefile

Create a Makefile with dev and build targets that match the project's real commands. The Makefile must use the repo's package manager and scripts.

Determine the package manager

1. Read package.json and check the packageManager field. Use it if present.
2. If missing, infer from lockfiles (prefer the most specific signal):
   • bun.lockb or bun.lock
   • pnpm-lock.yaml
   • yarn.lock
   • package-lock.json
3. If multiple signals exist or none are found, ask the user before proceeding.

Determine dev and build commands

1. Read package.json scripts in the project root that owns the app (monorepos usually define root scripts that proxy to packages).
2. Use dev for development and build for builds when available.
3. If a script is missing, search for a clear alternative (start, serve, preview, or framework docs) and confirm with the user when ambiguous.
4. Form the command using the package manager:
   • Bun: bun run <script>
   • Pnpm: pnpm <script>
   • Yarn: yarn <script>
   • Npm: npm run <script>

Create or update Makefile

• Create or update Makefile in the repo root.
• Add .PHONY: dev build.
• dev runs the resolved dev command.
• build runs the resolved build command.
• Do not leave placeholders; write the final commands.
• Preserve any existing targets not related to dev or build.

Stop and ask when needed

If the package manager or commands cannot be determined confidently, stop and ask the user for clarification before editing files.