This is a long blog post ending with a preview to "future installments of the guide" to use nix, while almost everything that you need to know with homebrew is `brew install/update/upgrade/uninstall`, and I have rarely run into any trouble with brew, and none at all in recent memory.
With nix, each project can define its own dependencies that have no impact on other projects. Combined with direnv, all you need is to `cd` into your project and you have the all of the dependencies at the right versions in your PATH.
Additionally, while definitely more complicated, nix (with nix-darwin and home-manager) can do way more than homebrew does. You can declaratively define pretty much the entire configuration for your machine.
I got a new Mac last week and with just a `git clone` and a few commands I had all my CLI tools installed, dotfiles setup, desktop apps installed, and even all of my macOS system settings configured.
(Maybe if you're already running NixOS and familiar with the latest it's a lot easier.)
I couldn't even uninstall it cleanly, since the Mac was new I gave up after some time and decided it was easier to reinstall macOS (which takes several hours but at least I can just leave it and then know that it's done).
So I'm back to (purely) brew (and scripts to `defaults write` etc.).
My frustration with brew is that it's getting increasingly opinionated, and those opinions are not familiar to me from any other OS/package manager... Like if you want postgres v15 you have to `brew install postgresql@15`, and then even if that's your only installed version it's 'keg-only', which means it's not on your PATH, and their suggestion is to dump some stuff at the end of your ~/.zshrc, which aside from the fact you're not using zsh and they could tell that, just seems dumb.
Then there's python & npm packages... They're deprecated and being removed as independent formulae, so don't do it like that. You're not allowed to install them with the python/node formula you installed, so don't do that. So what do you do, `python -m venv ~/system-python-venv` or something, activate it, and install in there. And now remember to activate that every time you want to use a command that happens to be a python package so you had to install it there. Or dump it in the end of your zshrc, I guess!
If you wanna give Nix-Darwin another go, I'm happy to help. Feel free to hit me up in the main Nix / NixOS channel or the Nix on macOS channel on Matrix. Getting everything working shouldn't take long with a little guidance.
(I can also help you get it cleanly uninstalled without reinstalling macOS, if you come away unsatisfied. I have manually uninstalled (i.e., not using the uninstaller) before.)
1) on install, nix-darwin complains about the nix.conf that determinate sets up
2) on uninstall, determinate complains about nix-darwin being installed
a. build darwin-rebuild from the Nix-Darwin flake
b. do a darwin-rebuild build --flake of the target system
c. delete all of the files Nix-Darwin will complain about colliding with upon first install, including `/etc/nix/nix.conf`
d. run the activation scripts in the built system directly, like
./result/activate-user
sudo ./result/activate
For (c), just inspect the files in `result/etc` (or wherever you put the symlink to your built system, or directly from the Nix store) and compare them to what already exists in `/etc`, e.g.,
find result/etc/ -type l | sed -E 's|^result||g' | xargs -I{} sh -c "test -f '{}' && echo '{}'"
2. Nix-Darwin has its own uninstaller whose job is to go remove all the references to `/etc/static` from `/etc` and some launchd crap, which are the bits and pieces that the Determinate Nix Installer finds and complains about when you try to uninstall Nix with an active Nix-Darwin installation. The uninstaller gets installed by default (try `less $(which darwin-uninstaller)`), but if it's missing for some reason you can also run it from the flake like `nix run github:LnL7/nix-darwin#darwin-uninstaller`.
This is what I used to do to appease the installer before. After some options changed and I was like 'you know what, I'm happy with the ones I set; if I have already built the system before I run the activation script, then it's fine to delete /etc/nix/nix.conf.'.
The Nix-Darwin installer isn't a great option for me anyway because it assumes your darwin-config will live in ~/.nixpkgs/darwin-configuration.nix, but I like to keep it in /etc/nix-darwin/configuration.nix for a more NixOS-like convention.