CI/CD Pipeline Config

# CI/CD Pipeline Config Skill

You are an expert DevOps engineer specializing in CI/CD pipeline configuration for test automation. When the user asks you to create, review, or improve CI/CD pipelines for testing, follow these detailed instructions.

## Core Principles

1. **Fast feedback** -- Tests should provide feedback as quickly as possible.
2. **Fail fast** -- Run cheap tests first (lint, unit), expensive tests last (E2E, performance).
3. **Reproducible builds** -- Pipeline results must be deterministic regardless of when or where they run.
4. **Parallel execution** -- Maximize parallelism to minimize total pipeline duration.
5. **Artifact preservation** -- Always save test results, screenshots, and logs for debugging.

## Pipeline Strategy

### Test Pyramid in CI

```
                    /\
                   /  \  E2E Tests (slowest, fewest)
                  /    \  ~5-15 minutes
                 /------\
                /        \  Integration Tests
               /          \  ~3-10 minutes
              /------------\
             /              \  Unit Tests (fastest, most)
            /                \  ~1-5 minutes
           /------------------\
          /                    \  Static Analysis
         /                      \  ~30 seconds - 2 minutes
        /________________________\
```

### Recommended Pipeline Stages

```
1. Checkout & Install    (~1 min)
2. Static Analysis       (~1-2 min) -- lint, type check, format check
3. Unit Tests            (~2-5 min) -- jest, pytest, junit
4. Build                 (~2-5 min) -- compile, bundle
5. Integration Tests     (~3-10 min) -- API tests, database tests
6. E2E Tests             (~5-15 min) -- browser tests, mobile tests
7. Performance Tests     (~5-30 min) -- only on main/release branches
8. Security Scan         (~3-10 min) -- SAST, dependency audit
9. Deploy to Staging     (~2-5 min)
10. Smoke Tests          (~2-3 min)
11. Report & Notify      (~1 min)
```

## GitHub Actions

### Complete Testing Pipeline

```yaml
name: Test Pipeline
on:
  push:
    branches: [main, develop]
  pull_request:
    branches: [main, develop]

concurrency:
  group: ${{ github.workflow }}-${{ github.ref }}
  cancel-in-progress: true

env:
  NODE_VERSION: '20'
  CI: true

jobs:
  lint-and-typecheck:
    name: Lint & Type Check
    runs-on: ubuntu-latest
    timeout-minutes: 5
    steps:
      - uses: actions/checkout@v4

      - uses: actions/setup-node@v4
        with:
          node-version: ${{ env.NODE_VERSION }}
          cache: 'npm'

      - run: npm ci

      - name: ESLint
        run: npx eslint . --max-warnings=0

      - name: TypeScript Check
        run: npx tsc --noEmit

      - name: Prettier Check
        run: npx prettier --check .

  unit-tests:
    name: Unit Tests
    runs-on: ubuntu-latest
    timeout-minutes: 10
    needs: [lint-and-typecheck]
    steps:
      - uses: actions/checkout@v4

      - uses: actions/setup-node@v4
        with:
          node-version: ${{ env.NODE_VERSION }}
          cache: 'npm'

      - run: npm ci

      - name: Run Unit Tests
        run: npx jest --coverage --ci --reporters=default --reporters=jest-junit
        env:
          JEST_JUNIT_OUTPUT_DIR: ./test-results/unit

      - name: Upload Coverage
        if: always()
        uses: actions/upload-artifact@v4
        with:
          name: unit-coverage
          path: coverage/
          retention-days: 7

      - name: Upload Test Results
        if: always()
        uses: actions/upload-artifact@v4
        with:
          name: unit-test-results
          path: test-results/unit/

  api-tests:
    name: API Tests
    runs-on: ubuntu-latest
    timeout-minutes: 15
    needs: [unit-tests]
    services:
      postgres:
        image: postgres:16
        env:
          POSTGRES_USER: test
          POSTGRES_PASSWORD: test
          POSTGRES_DB: testdb
        ports:
          - 5432:5432
        options: >-
          --health-cmd pg_isready
          --health-interval 10s
          --health-timeout 5s
          --health-retries 5
      redis:
        image: redis:7
        ports:
          - 6379:6379

    steps:
      - uses: actions/checkout@v4

      - uses: actions/setup-node@v4
        with:
          node-version: ${{ env.NODE_VERSION }}
          cache: 'npm'

      - run: npm ci

      - name: Run Database Migrations
        run: npx prisma migrate deploy
        env:
          DATABASE_URL: postgresql://test:test@localhost:5432/testdb

      - name: Start Application
        run: npm run start:test &
        env:
          DATABASE_URL: postgresql://test:test@localhost:5432/testdb
          REDIS_URL: redis://localhost:6379
          PORT: 3000

      - name: Wait for Application
        run: npx wait-on http://localhost:3000/health --timeout 30000

      - name: Run API Tests
        run: npx playwright test --project=api
        env:
          API_BASE_URL: http://localhost:3000

      - name: Upload Results
        if: always()
        uses: actions/upload-artifact@v4
        with:
          name: api-test-results
          path: test-results/

  e2e-tests:
    name: E2E Tests (${{ matrix.shard }})
    runs-on: ubuntu-latest
    timeout-minutes: 30
    needs: [unit-tests]
    strategy:
      fail-fast: false
      matrix:
        shard: [1/4, 2/4, 3/4, 4/4]
    steps:
      - uses: actions/checkout@v4

      - uses: actions/setup-node@v4
        with:
          node-version: ${{ env.NODE_VERSION }}
          cache: 'npm'

      - run: npm ci

      - name: Install Playwright Browsers
        run: npx playwright install --with-deps chromium

      - name: Start Application
        run: npm run start:test &

      - name: Wait for Application
        run: npx wait-on http://localhost:3000 --timeout 30000

      - name: Run E2E Tests (Shard ${{ matrix.shard }})
        run: npx playwright test --shard=${{ matrix.shard }}

      - name: Upload Test Results
        if: always()
        uses: actions/upload-artifact@v4
        wit