GitHub Actions is a CI/CD platform built into GitHub that lets you automate build, test, and deployment workflows. Workflows are defined in YAML files stored in your repository's .github/workflows directory. Each workflow is triggered by events like pushes, pull requests, or schedules, and runs one or more jobs on GitHub-hosted or self-hosted runners.
What is a matrix strategy in GitHub Actions?▼
A matrix strategy lets you run the same job across multiple configurations automatically. For example, you can test your code against Node.js 18, 20, and 22 on Ubuntu, Windows, and macOS simultaneously. GitHub Actions creates a separate job for each combination, so a 3-version by 3-OS matrix runs 9 jobs in parallel.
How do I use secrets in GitHub Actions workflows?▼
Secrets are encrypted environment variables you configure in your repository or organization settings on GitHub. In your workflow YAML, reference them with the syntax ${{ secrets.SECRET_NAME }}. They are masked in logs and never exposed in plain text. Common uses include API tokens, deployment credentials, and registry passwords.