Designing particle accelerators does come with its challenges. One of those is the very long life of the project. In this talk we're going to discuss how we're using both Nix and NixOS, and most notably its reproducibility properties to go the distance, and some of the difficulties we've encountered so far. In this presentation I'm going to present: the particle accelerator project the software components that goes inside, and the EPNix packaging project how we integrated those components with Nix and NixOS how we can cache dependencies to ensure their availability