ci-cd-and-automation

CI/CD and Automation

Overview

Automate the path from code to production. CI/CD pipelines give every change a consistent, repeatable journey through testing, validation, and deployment. The goal is a pipeline where passing tests is sufficient confidence to deploy — not a process that needs to be worked around.

When to Use

• Setting up a new project's CI/CD pipeline
• Adding automated testing to an existing pipeline
• Configuring deployment automation
• Setting up infrastructure as code
• Adding security scanning or quality gates
• Implementing preview environments for PRs

Pipeline Architecture

The Four Stages

┌─────────┐    ┌─────────┐    ┌──────────┐    ┌─────────────┐
│   CI    │    │  Test   │    │ Security │    │   Deploy    │
│         │───▶│         │───▶│          │───▶│             │
│ Build   │    │ Unit    │    │ Audit    │    │ Staging     │
│ Lint    │    │ Integr. │    │ SAST     │    │ Production  │
│ Types   │    │ E2E     │    │ Secrets  │    │ (gated)     │
└─────────┘    └─────────┘    └──────────┘    └─────────────┘
     ↑               ↑               ↑               ↑
  Every push    Every push    Every push     Main only

Stage Principles

• Fast feedback first: Lint and type-check before running slow tests
• Fail fast: Stop the pipeline at the first failure
• Parallel where safe: Run independent jobs concurrently
• Deterministic: Same commit always produces same result
• Cached: Restore dependencies from cache before installing

GitHub Actions Examples

Basic CI Pipeline

# .github/workflows/ci.yml
name: CI

on:
  push:
    branches: [main]
  pull_request:
    branches: [main]

jobs:
  quality:
    name: Quality Checks
    runs-on: ubuntu-latest

    steps:
      - name: Checkout
        uses: actions/checkout@v4

      - name: Setup Node.js
        uses: actions/setup-node@v4
        with:
          node-version: '20'
          cache: 'npm'

      - name: Install dependencies
        run: npm ci

      - name: Type check
        run: npm run type-check

      - name: Lint
        run: npm run lint

      - name: Unit tests
        run: npm run test:unit -- --coverage

      - name: Upload coverage
        uses: codecov/codecov-action@v4
        with:
          token: ${{ secrets.CODECOV_TOKEN }}

  build:
    name: Build
    runs-on: ubuntu-latest
    needs: quality

    steps:
      - uses: actions/checkout@v4
      - uses: actions/setup-node@v4
        with:
          node-version: '20'
          cache: 'npm'
      - run: npm ci
      - run: npm run build

      - name: Upload build artifact
        uses: actions/upload-artifact@v4
        with:
          name: build
          path: dist/
          retention-days: 7