{ 

  # INFORMATION
  # When building for a system, remember to change the hostname variable below

  description = "NixOS System Config";

  inputs = {
    # NixOS packages
    nixpkgs.url = "nixpkgs/nixos-23.05";

    # Manage dotfiles in a home directory
    home-manager.url = "github:nix-community/home-manager/release-23.05";
    home-manager.inputs.nixpkgs.follows = "nixpkgs";

    # Secureboot Configuration
    lanzaboote.url = "github:nix-community/lanzaboote";
    lanzaboote.inputs.nixpkgs.follows = "nixpkgs";
  };

  outputs = { nixpkgs, home-manager, lanzaboote, ... }:
  let
    hostname = "nixos-laptop";
    system = "x86_64-linux";
    pkgs = import nixpkgs {
      # Tells Flake what OS version we are using
      inherit system;
      config = { allowUnfree = true; };
    };

    lib = nixpkgs.lib;
  in {
    # Set up users with home-manager
    homeManagerConfigurations = {
      # Configuration for user "Albert"
      albert = home-manager.lib.homeManagerConfiguration {
        inherit system pkgs;
        username = "albert";
        homeDirectory = "/home/albert";
        configuration.imports = [ ./users/albert/home.nix ];
      };
      # Configuration for user "root"
      root = home-manager.lib.homeManagerConfiguration {
        inherit system pkgs;
        username = "root";
        homeDirectory = "/root";
        configuration.imports = [ ./users/rootd/home.nix ];
      };
    };

    # NixOS Configuration files:
    networking.hostname = "${hostname}";
    nixosConfigurations = {
      # Declare the configuration for "nixos-laptop":
      nixos-laptop = lib.nixosSystem { 
        inherit system hostname;
        modules = [
          # Hardware Configuration
          ./laptop/lenovo-p1.nix

          # SecureBoot Configuration
          lanzaboote.nixosModules.lanzaboote

          # NixOS Configuration file
          ./configuration.nix

          # Tell home-manager to use both global and user packages:
          home-manager.nixosModules.home-manager {
            home-manager.useGlobalPkgs = true;
            home-manager.useUserPackages = true;
          }
        ]; # modules
      }; # lib.nixosSystem - nixos-laptop

      # Declare the configuration for "nixos-p1", my laptop:
      nixos-desktop = lib.nixosSystem { 
        inherit system hostname;
        modules = [
          # Hardware Configuration
          ./desktop/desktop.nix

          # SecureBoot Configuration
          lanzaboote.nixosModules.lanzaboote

          # NixOS Configuration file
          ./configuration.nix

          # Tell home-manager to use both global and user packages:
          home-manager.nixosModules.home-manager {
            home-manager.useGlobalPkgs = true;
            home-manager.useUserPackages = true;
          }
        ]; # modules
      }; # lib.nixosSystem - nixos-laptop

    }; # nixosConfiguration
  };
}