I've gone full NixOS on my laptop and my gaming/homeserver desktop. I love it (even if there are parts I hate) and will never move to anything "less declarative". 100% no regrets.

However, I only recommend it with the caveat that the practical benefits are not worth the time invested and it's only worth it as a fun hobby. I think an immutable desktop like Silverblue/Bazzite is really the sweet spot.

Nix (non-OS) as a way to define dev environments though? Incredible, would recommend it in a heartbeat. Opening a project and knowing you are going to have the exact versions of all dependencies you need is so refreshing, or seeing that a public git repo has a `flake.nix` and being able to `nix run <url>` and download/build the project in one command is truly magic.