> My main issue with Arch was that after installing and trying stuff it left OS dirty even after package removal

Yeah, that's literally a problem with every single OS that is not NixOS (or, shoutout, Guix, or the other Nix-based variants).

That's also why I am sticking with NixOS. Been at least 5 years now- it's wonderful having a reliable LINUX system as my daily driver (or one of them).

And you can reboot into any old configuration! Even more insurance against fuckups!

> I am finally settling on it be the last OS I need

Same here. As soon as I got everything set up just how I like it in a declarative, reproducible fashion, I had this feeling of... "OK, this is great. I can't see a reason to ever leave this."