nixfiles

Nix code that is responsible for managing the configuration and environment of my personal machines.

Mostly documented for my own sake. I am trapped in a prison of my own design.

Bringup

Warning

This procedure has only been tested on Macs with Apple silicon.

Important

nix-darwin configurations will only work if your hostname matches a corresponding configuration in flake.nix.

1. Install Nix:

   sh <(curl -L https://nixos.org/nix/install)
   

   The installer will describe what it intends to do before prompting you to continue. However, in general, it:

   • Creates a new APFS volume for the Nix store.
   • Creates and registers Launch Daemons that mount the volume and spawn the Nix daemon.
   • Downloads and unpacks Nix.
   • Creates Nix build users and groups.
   • Writes the necessary shell profiles to make Nix usable.

2. Clone this repository to ~/src/prj/nixfiles. (As you might guess, this path is also hardcoded. For now. Maybe.)

3. Pop open a fresh shell so the computer knows where nix lives. Then, bootstrap Home Manager and nix-darwin:

   nix run home-manager/master -- switch --flake ~/src/prj/nixfiles
   nix run nix-darwin -- switch --flake ~/src/prj/nixfiles
   

   You will likely have to mess with some files in /etc to let nix-darwin manage the environment.

4. Change your shell:

   sudo chsh -s ~/.nix-profile/bin/fish $USER
   

5. If you set up nix-darwin, then you probably have two Nix installations now, which needs to be somehow fixed.

   (Nix is required to bootstrap nix-darwin, but nix-darwin essentially acts as a Nix installation in and of itself by managing a Nix daemon for you. Furthermore, a nix-darwin module is used to version-manage Nix, which will conflict with the Nix binary that was previously used to bootstrap this entire setup.)

   • Use nix doctor to verify that you don't have conflicting nix binaries in your PATH.
   • Use launchctl to ensure that you only have a single Nix daemon (e.g. launchctl print system, launchctl disable system/…, etc.)

6. All done.

Usage

This repository is a flake mostly because it makes pinning dependencies easier. However, flake.nix doesn't do much; in fact, it can largely be boiled down to:

outputs = inputs: {
  packages.aarch64-darwin.homeConfigurations.skip = import ./home/bootstrap.nix {
    inherit inputs;
    system = "aarch64-darwin";
    username = "skip";
  };

  packages.x86_64-linux.homeConfigurations.skip = import ./home/bootstrap.nix {
    inherit inputs;
    system = "x86_64-linux";
    username = "skip";
  };

  # ... etc. ...
};

To instantiate the homeManagerConfiguration outside of a flake context, home/bootstrap.nix can be used like so:

import "${<nixfiles>}/home/bootstrap.nix" {
  system = "aarch64-darwin";
  inputs = {
    inherit nixpkgs home-manager; # etc.
  };
  server = "infer"; # all Macs are workstations
};

Check out that file for more details.