If you’ve been working with LaTeX in Docker containers, you know the pain of waiting for builds and dealing with massive image sizes. I recently made the switch from TeX Live to Tectonic for my LaTeX Docker container, and the results have been nothing short of amazing. Let me share why this change has been such a game-changer for my workflow.

The Problem with TeX Live

Don’t get me wrong. TeX Live is an incredible project that has served the LaTeX community well for years. But when it comes to Docker containers, it comes with some serious drawbacks:

  • Build time: My old TeX Live setup took over 5 minutes to build
  • Image size: The resulting container weighed in at a hefty 2.3GB

For modern development workflows where you want quick iterations and lean containers, these numbers just don’t cut it anymore.

Enter Tectonic

Tectonic is a modernized, complete TeX/LaTeX engine that’s been converted into a standalone library. It is derived from XeTeX and uses support files from the TeX Live project, so you’re still getting that rock-solid LaTeX foundation you trust.

The difference? The implementation is streamlined and optimized for exactly the kind of use case I needed.

The Numbers Don’t Lie

After switching to Tectonic, my Docker container stats improved dramatically:

  • Build time: Just 50 seconds (down from 5+ minutes!)
  • Image size: Only 124MB (down from 2.3GB!)

That’s an 85% reduction in build time and a 95% reduction in image size. These are not just numbers! They translate to real productivity gains. I always hated rebuilding my LaTex container, now it is not even a bother.

One Small Trade-off: Package Caching

There is one thing I had to do differently with Tectonic that wasn’t necessary with TeX Live: preloading package caches. By default, Tectonic downloads required packages at runtime, which can slow down the build process. To address this, I created a “preload” tex file that includes the most common packages I use.

This ensures that those packages are already cached in the Docker container, eliminating download time during actual builds. It’s a small bit of extra setup, but totally worth it for the performance gains.

The Bottom Line

If you’re running LaTeX in Docker containers and haven’t tried Tectonic yet, I highly recommend giving it a shot. The combination of faster builds, smaller images, and a modern approach to LaTeX compilation makes it an easy win for containerized workflows.

The future of LaTeX tooling is here. And it’s Rust!

If you want to use my Dockerfile that I use for this container; check out Github. And if you have any suggestions, find me on Bluesky.