gistfile1.nix

{ pkgs, ... }:

{
  boot.loader.grub.extraEntries = ''
    menuentry "Nixos with custom kernel" {
      linux ($drive1)/rescue-kernel init=${config.system.build.toplevel}/init ${toString config.boot.kernelParams}
      initrd ($drive1)/rescue-initrd
    }
  '';
  boot.loader.grub.extraFiles = {
    "rescue-kernel" = /home/custom/bzImage;
    "rescue-initrd" = "${config.system.build.initialRamdisk}/initrd";
  };
}