Building an Elixir Release into a Docker image using GitLab CI - Part 1

What this post added

This post details the implementation of a CI/CD pipeline for building Elixir releases into Docker images. It outlines the `.gitlab-ci.yml` configuration, including stages for build, styles, test, release, and cleanup. Specific technical details include the use of `docker:latest` image, custom Dockerfiles (`Dockerfile.build` and `Dockerfile`), volume management for build artifacts, manual linking of services like PostgreSQL, and the process of building and pushing the release image to the GitLab Container Registry. It also touches upon using environment variables for configuration and the `mix release` command for creating the Elixir release artifact.