Generally, Nix's strength is allowing for reproducing software behaviour, yeah. I'd say NixOS's declarative config more/less covers the config files, where on

Generally, Nix's strength is allowing for reproducing software behaviour, yeah. I'd say NixOS's declarative config more/less covers the config files, where on non-NixOS you'd edit the files under /etc (and hope you didn't break anything). Whereas, Home Manager's declarative config is more/less the stuff underneath $HOME or the XDG config dir. Turns out that a few things with fish shell don't work with a purely declarative config. (e.g. the universal environment variables are stateful). For myself, I don't rely on writing all my configuration in Nix files. I configure fish shell using config.fish. (Though I do use HM to symlink the config file).