CI/CD & Deployment Pipelines
Continuous integration, continuous deployment, infrastructure as code, and reliable deployment strategies
CI (Continuous Integration): code changes trigger automated builds and tests. Benefits: catch bugs early (seconds vs hours), enable rapid iteration, reduce integration conflicts.
Build pipeline: developer commits code -> version control webhook triggers -> build server clones repo -> build (compile, test, static analysis) -> artifact creation (Docker image, binary, JAR).
Testing stages: unit tests (fast, <1 sec each), integration tests (slower, 1-10 sec), E2E tests (slowest, 10-60 sec). Quality gates: block merge if tests fail or coverage drops, enforce code style checks via linters.
Artifacts: immutable, versioned outputs (Docker images tagged with commit SHA). Tools: Jenkins (open-source), GitHub Actions, GitLab CI, CircleCI, AWS CodePipeline.
Real-world: Google runs 100k+ CI builds/day; GitHub Actions free for open-source; Netflix auto-tests every change before considering for deployment.
Key Takeaways
Visual Diagram
Commit -> Webhook -> Build -> Unit Tests -> Integration Tests -> E2E -> Artifact (Docker image)