nixos-config/modules/system/boot/default.nix

{ ... }:
{
  boot.loader.systemd-boot.enable = true;
  boot.loader.efi.canTouchEfiVariables = true;
  boot.plymouth.enable = true;
  boot.plymouth.theme = "bgrt";
  boot.consoleLogLevel = 0;
  boot.kernelParams = [ "quiet" "udev.log_level=0" ];
  boot.initrd.verbose = false;
  boot.lanzaboote = {
    enable = true;
    pkiBundle = "/etc/secureboot";
  };
}