Short answer
Continuous integration merges changes frequently and verifies each one automatically with builds and tests. Continuous delivery keeps every passing build deployable; continuous deployment releases it automatically. A good pipeline is fast, reproducible and trustworthy: cached builds, meaningful test stages, security checks, immutable artefacts promoted between environments, and safe rollouts with quick rollback.
Typical stages
- Lint, type-check and unit tests on every commit.
- Build a versioned, immutable artefact once.
- Integration and end-to-end tests against the artefact.
- Deploy progressively — canary or blue/green — with automated health checks.
How to answer it in an interview
- Mention flaky tests and how you would quarantine them.
- Talk about secrets management in pipelines.