1.1What CI/CD Actually Means

Continuous Integration (CI) is the practice of merging code changes into a shared branch frequently -- at least once a day -- and validating each merge with automated builds and tests. The key word is "continuous." If you merge once a week after a marathon of local development, you are not doing CI regardless of how many tools you have installed.

Continuous Delivery (CD) extends CI by ensuring that the codebase is always in a deployable state. Every commit that passes the pipeline could be released to production at the push of a button.

Continuous Deployment goes one step further: every commit that passes the pipeline is automatically deployed to production with no human intervention.

Most teams practice CI and Continuous Delivery. Full Continuous Deployment requires an exceptionally mature test suite and monitoring infrastructure. This book will prepare you for all three.