{
  config,
  lib,
  pkgs,
  ...
}:

{
  imports = [ ];

  options.me = {
    nix_index.enable = lib.mkOption {
      type = lib.types.bool;
      default = false;
      example = true;
      description = "Whether we want to install nix_index.";
    };
  };

  config = lib.mkIf config.me.nix_index.enable (
    lib.mkMerge [
      {
        environment.systemPackages = with pkgs; [
          nix-index-unwrapped
        ];

        environment.persistence."/state" = lib.mkIf (!config.me.buildingIso) {
          hideMounts = true;
          users.talexander = {
            directories = [
              {
                directory = ".cache/nix-index";
                user = "talexander";
                group = "talexander";
                mode = "0755";
              }
            ];
          };
        };

      }
    ]
  );
}