A few weeks ago I ran nix flake update to get the latest versions of CLI tools that I regularly use from nixos-unstable. atuin is one of those tools which I started using relatively recently and quickly became a huge fan of. I run it on all of my machines, and I can’t overstate how amazing it is to have all of my shell history across all of my machines synced.

After learning how to add an unstable overlay to nixpkgs, being able to override individual service modules from unstable was something that I still struggled with until fairly recently. Hopefully this helps someone else looking to do common-but-not-very-obvious operation.