I'm getting a lot of mileage converting all my little VMs and containers over to NixOS. Entirely using AI, Claude Code is remarkably good at creating Nix flakes. The declarative OS is a good match for LLM generation of system specs. No side effects of commands to track, everything testable and reproducible by the agent. And NixOS itself works quite well. Most of the packages I need are there and if something's missing Claude doesn't seem to have any problem making it itself.