I wish guides like these contained screenshots.

Do people use Nix for desktop OSes? As a VM they SSH into? A collection of config scripts that they don't directly issue commands to?

I certainly can't tell from a quick glance of this guide

Nix is pretty usable for both desktops and headless servers. Personally, I even use it on macOS without much trouble.

My system looks like any other install of Ventura, but all of my configuration, ranging from the terminal and VS Code to macOS-specific system preferences and Safari, is done declaratively in Nix [1]. The overwhelming majority of my installed software also comes from Nix packages, with some exceptions for stuff that is not packaged yet (e.g., I have Podman Desktop, the macOS ZFS port, Lulu, yubikey-manager-qt installed through Homebrew -- fortunately nix-darwin [2] also just lets me have an set of brews/casks in my config).

It was been a bit of a nightmare at first since the error messages are kind of horrific, and there can be a lack of good examples/docs on flakes. But I think the weekend worth of time I invested was worth it since I no longer need to rely on hacky shellscripts or remember to manually configure anything.

[1]: <https://github.com/nix-community/home-manager>

[2]: <https://github.com/LnL7/nix-darwin>