@mhoye @michaelcoyote I think that's what #SnowflakeOS https://snowflakeos.org/ is trying to do.
Their nix-software-center: A simple gtk4/libadwaita software center to easily install and manage nix packages https://github.com/snowfallorg/nix-software-center#readme would really have made life easier for the OP... at least in the getting started phase.