I’ve been using it for over a year and love it. A config file for your entire system, and built in rollbacks anytime something goes wrong. One language to configure everything, although in practice that doesn’t always work. But I love it.

Some others have started why it works, here is some how. Nixos completely disregards the fhs. Packages don’t install to anywhere standard, every package and configuration change gets it’s on directory in /nix/store but through smart use of tracking everything there, it symlinks all those files to proper places and sets up the environment for them to know where libraries are.

This is then also why you don’t need sudo privileges to install things. Your profile has an environment that is aware of your users packages and configurations, the system itself isn’t effected because everything is symlinked.

Then because every update means new directories in /nix/store you can role back to your last configuration because plasma broke something or whatever.

However, it’s a LOT to learn. Best place I know of is https://piped.video/watch?v=AGVXJ-TIv3Y&t=0

This guy did a good job for me. Hope this helps!