Turborepo

Here’s a complete Turborepo setup for a fictional project called **EcoTrack**, a sustainability analytics platform with 4 packages: `core`, `ui`, `api`, and `cli`. We’ll use **pnpm** as the package manager and configure caching for `build`, `test`, and `lint` tasks. The CI/CD pipeline will run on GitHub Actions with Turborepo’s remote caching enabled.

### Monorepo Structure
```
ecotrack/
├── apps/
│   └── web/          # Next.js frontend
├── packages/
│   ├── core/         # Shared business logic
│   ├── ui/           # React component library
│   ├── api/          # REST API service
│   └── cli/          # CLI tool for data processing
├── package.json
├── pnpm-workspace.yaml
├── turbo.json        # Turborepo config
└── .github/workflows/ci.yml
```

### turbo.json Configuration
```json
{
  "$schema": "https://turbo.build/schema.json",
  "pipeline": {
    "build": {
      "dependsOn": ["^build"],
      "outputs": ["dist/**", ".next/**"]
    },
    "test": {
      "dependsOn": ["^build"],
      "outputs": []
    },
    "lint": {
      "outputs": []
    }
  }
}
```

### GitHub Actions CI Pipeline
```yaml
name: CI
on: [push, pull_request]
jobs:
  test:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - uses: pnpm/action-setup@v2
        with:
          version: 8
      - uses: actions/setup-node@v4
        with:
          node-version: 20
          cache: 'pnpm'
      - run: pnpm install --frozen-lockfile
      - run: pnpm turbo run build --filter=... --dry=json > output.json
      - run: pnpm turbo run test lint
```

### Key Commands
- `pnpm turbo run build --filter=web` – Build only the `web` app and its dependencies.
- `pnpm turbo run test --parallel` – Run tests in parallel across all packages.
- `pnpm turbo prune --scope=ui` – Generate a minimal subset of the monorepo for deployment.

### Expected Performance Gains
- **First build (cold cache)**: ~2m 30s
- **Subsequent builds (cached)**: ~15s (90% reduction)
- **Parallel test runs**: 4x faster than sequential execution.

### Next Steps
1. Push the changes to GitHub and observe the CI pipeline.
2. Monitor cache hits in the Turborepo logs.
3. Integrate with Prometheus (via `turborepo-remote-cache-metrics`) to track cache efficiency in your DevOps dashboard.