Automate with GitHub Actions

What it is

GitHub Actions is GitHub’s built-in automation. A workflow is a YAML file in .github/workflows/ that lists jobs and steps, and the events that start them.

How it works

1. Pick a trigger: push, pull_request, schedule (cron) or workflow_dispatch (a manual button), among many events.
2. Define jobs that run on GitHub-hosted runners: install, build, test, deploy.
3. Store credentials (API keys, deploy tokens) as Actions secrets, never in the file. GitHub doesn’t pass secrets to workflows triggered from forked repositories.
4. Gate merges by requiring the workflow’s status checks to pass before a pull request can merge (a protected-branch rule; in private repositories that needs a paid plan).
5. Let agents help: coding agents can write and fix workflows; GitHub’s MCP server lets agents list runs and read logs to diagnose failures.

Common business uses: build and check a website on every pull request; fail a build if broken links or missing fields appear; publish on merge; run a weekly report script.

Benefits

• Repeatable checks catch mistakes before they go live.
• Deploys happen the same way every time.
• Scheduled jobs replace fragile manual routines.

Limits and risks

• Workflows with secrets are a security surface; limit permissions and review changes.
• Hosted minutes are metered for private repositories: GitHub Free includes 2,000 minutes a month and Pro and Team 3,000, with extra use billed. Public repositories run free.
• Third-party actions run code in your pipeline; pin versions and use trusted sources.