In 30 seconds
- Integrate small changes at least daily.
- Every change triggers an automated build and test run.
- Fix a broken build immediately.
Core practices
- Merge to the main branch at least once a day
- Automated build and tests on every change
- Keep the build fast, ideally under ten minutes
- Fix a broken build before anything else
Grady Booch used the term in 1991; Extreme Programming made daily integration a core practice.
Why it matters
Integration problems grow the longer branches live apart. Merging small changes often keeps conflicts tiny and gives fast feedback. It's the foundation for continuous delivery.
Common mistakes
- Running a CI server but keeping long-lived branches
- Ignoring red builds
- Slow builds that people stop waiting for
Myth vs reality
Myth · Having a CI tool means doing CI.
Reality · CI is a practice: integrating often.
Myth · Feature branches are fine if CI runs on them.
Reality · Long-lived branches still integrate late.
Myth · A broken build can wait.
Reality · It blocks everyone; fix it first.
The AI angle
AI increases the volume of changes. Fast CI with strong checks becomes the safety net that catches AI mistakes before they reach the main branch.
FAQ
How often should we integrate?
At least daily; many teams do it several times a day.
What should the build include?
Compilation, unit tests and fast integration tests.
How does CI relate to DevOps?
It's one of the foundational DevOps practices.