GitLab CI is a pain to build Docker images with because of the tradeoffs you have to make to get it done. We wrote a blog post that talks about these tradeoffs, and how they can cause build times to explode and open security holes that you would rather keep closed. Depot makes this much simpler because your image builds get routed to our remote builders with a persistent cache. So, you can build your images without Docker-in-Docker (dind) and full root permissions.

You can read the blog post or check out our new GitLab CI integration guide.