GitLab CI Pipelines

GitLab CI is GitLab's integrated continuous integration/deployment platform. Pipelines are defined in .gitlab-ci.yml (YAML) and trigger automatically on push, merge request, schedule. Key features: built-in container registry (push Docker images), Kubernetes integration, artifact caching, protected environments, runners (shared or self-hosted). Pipelines consist of stages (build, test, deploy) and jobs within each stage. Jobs can run in parallel or sequentially with dependencies. Output is artifacts (compiled binaries, reports) and deployment to environments (staging, production).