CI/CD is how modern teams ship changes quickly without treating every release like a gamble. It breaks down into two parts: Continuous Integration (CI) and Continuous Delivery/Deployment (CD).
Continuous Integration (CI)
- Frequent merges: Developers merge to main often, avoiding long-lived branches and painful conflicts.
- Automated checks: Each merge triggers builds, tests, security scans, and linting.
- Fast feedback: CI tells you quickly if a change is safe to promote or needs fixing.
Continuous Delivery vs. Continuous Deployment
- Continuous Delivery: Every change that passes CI is deployable. You still choose when to push to production (often with an approval gate).
- Continuous Deployment: Every change that passes CI automatically rolls out to production—no manual approval. Feature flags and guardrails are essential here.
Why CI/CD matters
- Smaller, safer releases: Frequent, small changes are easier to review, test, and roll back.
- Reduced toil: Manual steps disappear; pipelines handle repeatable work.
- Higher quality: Tests and scans catch issues early; fewer surprises in production.
- Visibility: Everyone sees build/deploy status and what’s live.
Core pieces of a CI/CD pipeline
- Source control hooks: On push/PR, trigger pipeline runs.
- Build & test: Compile, run unit/integration tests, static analysis, and security scans.
- Artifact management: Produce versioned artifacts (images/packages) and store them once.
- Environment promotion: Reuse the same artifact in stage and prod; avoid rebuilding per env.
- Deploy + health checks: Apply manifests, run migrations carefully, and verify with readiness/smoke tests.
- Rollbacks: Quick path back to the previous version if health checks fail.
Good practices
- Keep pipelines as code; review them like application changes.
- Make CI fast and reliable; flaky tests block trust.
- Use feature flags to separate deploy from release.
- Protect main: required reviews, tests, and scan gates.
- Watch metrics: build duration, failure rate, deploy frequency, and MTTR.
Getting started
- Automate build/test on every push and PR.
- Create a staging deploy with smoke tests and health checks.
- Adopt artifact promotion and add a prod gate (approval or canary/blue-green).
- Introduce feature flags and rollback playbooks.
When CI/CD is in place, releases become routine instead of risky. You ship faster, with fewer surprises, and the whole team sees what’s live.