CI/CD
CI/CD is the automated pipeline that tests and ships code — Continuous Integration runs tests on every change before it merges, and Continuous Delivery/Deployment automatically pushes tested code toward (or into) production instead of a person doing it by hand.
Continuous Integration (CI) is the practice of merging code changes frequently — multiple times a day, not once a week — with an automated pipeline running tests on every change. The point is catching a broken build or a failing test within minutes of it being introduced, while the change is small and fresh in the author’s mind, instead of discovering it days later tangled up with five other people’s changes.
Continuous Delivery means every change that passes CI is automatically packaged and made ready to deploy, with a human clicking a button to actually release it. Continuous Deployment goes one step further and skips the button — every change that passes all checks goes to production automatically. Most teams use “CI/CD” loosely to mean either, and the real distinction (manual release gate or not) matters more in practice than the terminology.
The tooling — GitHub Actions, GitLab CI, CircleCI, Jenkins — is rarely the hard part. Most give small teams a generous free tier. The actual engineering work is designing a pipeline that stays fast and maintainable as the number of repositories and services grows, which is a different problem than getting one app to deploy automatically.
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