GitHub

1. About pull requests

   Opening PRs, base and compare branches, draft PRs, diffs, discussion.

2. Pull request reviews

   Review comments, approvals, requested changes, required reviews.

3. Merging pull requests

   Merge commit, squash merge and rebase merge, merge queue, auto-merge.

4. Code owners

   CODEOWNERS file, automatic review requests, required owner review.

5. Protected branches

   Branch protection rules: required status checks, required reviews, force-push restrictions, linear history.

6. Rulesets

   Repository and organization rulesets, enforcement, bypass actors, targeting branches and tags.

7. Understanding GitHub Actions

   Workflows, events, jobs, steps, runners, actions and reusable components.

8. Workflow syntax

   YAML syntax: on, jobs, needs, matrix strategy, if conditions, permissions, concurrency, env.

9. Events that trigger workflows

   push, pull_request, workflow_dispatch, schedule, pull_request_target, workflow_run and event payloads.

10. Secrets in Actions

    Repository, environment and organization secrets, GITHUB_TOKEN, masking, safe usage.

11. Webhooks

    Webhook events and payloads, delivery, redelivery, configuring endpoints.

12. Validating webhook deliveries

    HMAC SHA-256 signature header X-Hub-Signature-256, webhook secrets, constant-time comparison.

13. GitHub Apps

    GitHub Apps vs OAuth apps, installation, fine-grained permissions, installation access tokens, JWT app authentication.

14. OAuth apps

    OAuth web flow, device flow, scopes, user access tokens.

15. REST API

    REST API basics, authentication, pagination, rate limits, API versioning.

16. Personal access tokens

    Fine-grained vs classic PATs, scopes, expiry, safe token handling.

17. Dependabot alerts

    Dependency vulnerability alerts, security updates, dependency graph.

18. Secret scanning

    Detecting leaked credentials, push protection, partner patterns.

19. Code scanning

    CodeQL static analysis, SARIF results, alerts on pull requests.

Each section links to the official page. Titles and summaries by Extra Credit; the docs belong to their authors.