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. I also self-host the atuin server, because why not? While I typically install my CLI tools from nixos-unstable, with services that I self-host I tend to be a little more conservative and run them from the latest stable release, which is currenly nixos-23.11. The atuin CLI tool had some database migrations as part of the v18 release that made it incompatible with servers running v17, which is what my self-hosted atuin server is running from nixos-23.11. Usually this would be a non-issue since most service modules in Nixpkgs have a package option that lets you override the package used for a service. However, unfortunately for the …

cross-posted from: https://lemmy.world/post/13113247

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.