Here's my Nix setup for my M1 Macbook using nix-darwin, if it helps anyone: https://github.com/dustinlyons/nixos-config
It's also interesting to hear comments from the Nix detractors here. There's ample room to criticize the language and even the design philosophy behind the package manager, but it's a shame that most people never give it a "proper shot". Maybe that's the fault of Nix maintainers though.
The main issue (I think) is that it boils down to "a worse shell script" shaped in a LISP kind of wrapper. Plenty of people know about LISP too but will simply not even look at it because it is too different. Even if you take away the functional paradigm it just doesn't look like anything that can map to an existing knowledge base. This is also why C-esque languages (and I'm talking about the non-edge-cases here) are so prevalent and successful; they don't have to be 'the best' or even 'good', they just have to be easy to map to existing knowledge to be useful. And Nix doesn't do that.