nixos-config/home-manager/flake-module.nix

{
  withSystem,
  lib,
  inputs,
  ...
}: {
  flake = withSystem "x86_64-linux" ({
    self',
    pkgs,
    ...
  }: let
    flattenAttrs = attrs:
      lib.listToAttrs (lib.flatten (lib.mapAttrsToList
        (
          outer_key:
            lib.mapAttrsToList
            (inner_key: value: {
              name = "${outer_key}-${inner_key}";
              inherit value;
            })
        )
        attrs));
    machines = import ./machines.nix;
    buildHomeManager = config: (inputs.home-manager.lib.homeManagerConfiguration {
      inherit pkgs;
      modules = [
        config
        inputs.emanote.homeManagerModule
        inputs.impermanence.nixosModules.home-manager.impermanence
      ];
    });
    buildModesForHost = host: modes:
      (pkgs.recursiveLinkFarm "${host}-modes"
        (lib.mapAttrs
          (_: config: (buildHomeManager config).activationPackage)
          modes))
      .overrideAttrs (old: {
        buildCommand =
          if inputs.self.sourceInfo ? rev
          then ''
            ${old.buildCommand}
            echo ${inputs.self.sourceInfo.rev} > $out/config-commit;
          ''
          else old.buildCommand;
      });
  in {
    homeConfigurations = lib.mapAttrs (_: buildHomeManager) (flattenAttrs machines);
    homeModes = lib.mapAttrs buildModesForHost {inherit (machines) zeus apollo;};
  });
}