Dramatically Improve Your Docker Build Time in GitLab CI

Make your containerized CI environments truly useful by accelerating your Docker builds

Photo by toine G on Unsplash

Modern software development cycle means packaging your applications often as a container. This task can be time consuming and may slow down your testing or deployment significantly. The problem is especially obvious in the context of a continuous integration and deployment process where images are built at every code modification.

In this article, we will discuss various ways of speeding up the build time of Docker images in a continuous integration pipeline by implementing different strategies.

Packaging a sample application locally

As an example, we will first take a Python Flask application. Cannot be simpler than that:

Writing the Dockerfile

Let’s write the corresponding Dockerfile: