{
  inputs = {
    home-manager = {
      url = "github:nix-community/home-manager/release-20.09";
      inputs.nixpkgs.follows = "/nixpkgs";
    };
    nixpkgs.url = "github:NixOS/nixpkgs/nixos-20.09";
    nixpkgs-master.url = "github:NixOS/nixpkgs";
    nixpkgs-unstable.url = "github:NixOS/nixpkgs/nixos-unstable";
    nixos-hardware.url = "github:NixOS/nixos-hardware/master";
  };

  outputs = { self, home-manager, nixpkgs, nixpkgs-master, nixpkgs-unstable
    , nixos-hardware }: {
      nixosConfigurations = let
        defaultModules = [
          home-manager.nixosModules.home-manager
          ./modules/g810-led.nix
          ./main/fonts.nix
          ./main/general.nix
          ./main/kernel.nix
          ./main/packages.nix
          ./main/printing.nix

          ({ config, lib, lib', ... }: {
            config = {
              _module.args = {
                lib' = lib // import ./lib { inherit config lib; };
                master = lib'.pkgsImport nixpkgs-master;
                unstable = lib'.pkgsImport nixpkgs-unstable;
              };

              nix.registry = {
                nixpkgs.flake = nixpkgs;
                nixpkgs-unstable.flake = nixpkgs-unstable;
              };

              nixpkgs.overlays = [ (import ./overlays) ];

              home-manager = {
                useGlobalPkgs = true;
                useUserPackages = true;
                users.dave.imports = [ ./home/default.nix ];
              };
            };
          })
        ];
      in {
        hephaestus = nixpkgs.lib.nixosSystem {
          system = "x86_64-linux";
          modules = [
            ./machines/hephaestus/configuration.nix
            ./machines/hephaestus/hardware.nix
          ] ++ defaultModules;
        };
        hermes = nixpkgs.lib.nixosSystem {
          system = "x86_64-linux";
          modules = [
            nixos-hardware.nixosModules.lenovo-thinkpad-t480s
            ./machines/hermes/configuration.nix
            ./machines/hermes/hardware.nix
          ] ++ defaultModules;
        };
      };
    };
}