CI/CD with GitHub Actions: Complete Guide

GitHub Actions provides powerful CI/CD directly in your repository. Here's how to use it effectively.

Basics

Workflow Structure

Workflows live in .github/workflows/ as YAML files with triggers, jobs, and steps.

Triggers

• push: On code push
• pull_request: On PR events
• schedule: Cron-based
• workflow_dispatch: Manual trigger

Common Workflows

Testing

Run tests on every push and pull request to main branch.

Build and Deploy

Build application and deploy to Vercel, Netlify, AWS, etc.

Docker Build

Build and push Docker images to container registries.

Best Practices

Use Caching

Cache dependencies to speed up workflows with actions/cache.

Secrets Management

Store sensitive data in GitHub Secrets, reference with secrets.NAME.

Matrix Builds

Test across multiple versions:

• Node versions
• Operating systems
• Database versions

Reusable Workflows

Create shared workflows for common patterns.

Security

Least Privilege

Use minimal permissions for tokens.

Pin Action Versions

Use specific versions, not @latest.

Review Third-Party Actions

Audit before using external actions.

Monitoring

Status Badges

Show workflow status in README.

Notifications

Slack/email notifications for failures.

Conclusion

GitHub Actions simplifies CI/CD. Start with testing, add deployment as confidence grows.