The kind of problem you're describing is what Nix handles exceptionally well. Don't install everything at the system level (NixOS). Home Manager is better suit

The kind of problem you're describing is what Nix handles exceptionally well. Don't install everything at the system level (NixOS). Home Manager is better suited for things like Claude. And even if you did choose to install Claude from your NixOS configuration, you can draw from a different Nixpkgs commit. Usually, using the latest stable channel for NixOS and nixpkgs-unstable for the rest is good enough.