NixOS only has nixpkgs modifications, not Ubuntu's, as much as Fedora doesn't have Ubuntu's modifications. My understanding is that packages available for Nix a

NixOS only has nixpkgs modifications, not Ubuntu's, as much as Fedora doesn't have Ubuntu's modifications. My understanding is that packages available for Nix are patched to work within its context, but otherwise kept as original as possible, with optional configuration switches.