DevOps with Kubernetes - Second Edition

Multi-stage builds

The principles we've discussed so far are all about how to make builds fast and how to make the final image smaller while keeping the maintainability of the Dockerfile. Instead of striving to optimize a Dockerfile, writing one to build the artifacts we need and then moving them to another image with runtime dependencies only makes it much easier to sort the different logic out. In the building stage, we can forget about minimizing the layers so that the build cache can be reused efficiently; when it comes to the release image, we can follow the previously recommended techniques to make our image clean and small. Before Docker CE 17.05, we had to write two Dockerfiles to implement this build pattern. Now, Docker has built-in ...