_: {
  flake.nixosModules.bootloader = {
    inputs,
    pkgs,
    ...
  }: {
    # grub theme
    boot.loader.grub = {
      theme = inputs.nixos-grub-themes.packages.${pkgs.system}.nixos; # if you want to use nixos grub theme
    };

    # Bootloader.
    boot.loader.systemd-boot.enable = true;
    boot.loader.efi.canTouchEfiVariables = true;
  };
}