CI-CD
Overview
CI/CD automates verification and delivery so changes can move safely and repeatedly.
Why It Matters
Automation catches issues early and makes release behavior more consistent.
Core Concepts
- Continuous integration proves the change builds and passes checks.
- Continuous delivery/deployment pushes the result toward users.
- Gates should match the risk level.
Mental Models
Automate the repetitive parts of trust.
Best Practices
- Make pipelines fast and visible.
- Keep checks stable.
- Differentiate build, test, and deploy concerns.
Common Mistakes
- Packing too much logic into one pipeline step.
- Ignoring flaky tests.
- Treating CI as a substitute for code quality.
Trade-offs
Stronger gating improves safety, but too much friction can slow the team and encourage bypasses.
Decision Framework
| Stage | Purpose |
|---|---|
| CI | Verify change quality |
| CD | Deliver the approved result |
| Post-deploy | Confirm real-world behavior |
Examples
- Run typecheck and tests before merging.
- Deploy only after verification passes.
Checklists
- Are checks fast enough to be used daily?
- Are failures easy to understand?
- Is deploy confidence validated after release?
Senior Engineer Notes
Senior engineers value pipeline signal quality. A slow or noisy pipeline is effectively broken.