nixos-config/modules/core/bootloader.nix

{ pkgs, ... }:
{
  boot = {
    kernelPackages = pkgs.linuxPackages_latest;
    loader = {
      systemd-boot.enable = true;
      efi.canTouchEfiVariables = true;
      systemd-boot.configurationLimit = 10;
    };
  };
}