{
  description = "My system configuration";

  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable";
    nix-darwin = {
      url = "github:LnL7/nix-darwin";
      inputs.nixpkgs.follows = "nixpkgs";
    };
  };

  outputs = inputs@{ self, nix-darwin, nixpkgs }:
    let
      configuration = { pkgs, ... }: {

        services.nix-daemon.enable = true;
        # Necessary for using flakes on this system.
        nix.settings.experimental-features = "nix-command flakes";

        system.configurationRevision = self.rev or self.dirtyRev or null;

        # Used for backwards compatibility. please read the changelog 
        # before changing: `darwin-rebuild changelog`.
        system.stateVersion = 4;

        # The platform the configuration will be used on.
        # If you're on an older system, replace with "x86_64-darwin"
        nixpkgs.hostPlatform = "aarch64-darwin";

        # Declare the user that will be running `nix-darwin`.
        users.users.$USER = {
          name = "$USER";
          home = "/Users/$USER";
        };

        security.pam.enableSudoTouchIdAuth = true;

        # Create /etc/zshrc that loads the nix-darwin environment. 
        programs.zsh.enable = true;
        environment.systemPackages = [ pkgs.neofetch ];

        homebrew = {
          enable = true;
          # onActivation.cleanup = "uninstall";

          taps = [ ];
          brews = [ "cowsay" ];
          casks = [ ];
        };
      };
    in
    {
      darwinConfigurations."$HOSTNAME" = nix-darwin.lib.darwinSystem {
        modules = [
          configuration
        ];
      };
    };
}