anchor.diff:  
       # Make our own efi program, we can't rely on "grub-install" since it seems to
       # probe for devices, even with --skip-fs-probe.
  -    ${pkgs.buildPackages.grub2_efi}/bin/grub-mkimage --directory=${grubPkgs.grub2_efi}/lib/grub/${grubPkgs.grub2_efi.grubTarget} -o $out/EFI/boot/boot${targetArch}.efi -p /EFI/boot -O ${grubPkgs.grub2_efi.grubTarget} \
  +    grub-mkimage --directory=${grubPkgs.grub2_efi}/lib/grub/${grubPkgs.grub2_efi.grubTarget} -o $out/EFI/boot/boot${targetArch}.efi -p /EFI/boot -O ${grubPkgs.grub2_efi.grubTarget} \
         $MODULES
       cp ${grubPkgs.grub2_efi}/share/grub/unicode.pf2 $out/EFI/boot/
   
  
positive.code:     ${refind}
    '';
  
    efiImg = pkgs.runCommand "efi-image_eltorito" { nativeBuildInputs = [ pkgs.buildPackages.mtools pkgs.buildPackages.libfaketime pkgs.buildPackages.dosfstools ]; }
      # Be careful about determinism: du --apparent-size,
      #   dates (cp -p, touch, mcopy -m, faketime for label), IDs (mkfs.vfat -i)
      ''
  
negative.code:   # Notes about grub:
    #  * Yes, the grubMenuCfg has to be repeated in all submenus. Otherwise you
    #    will get white-on-black console-like text on sub-menus. *sigh*
    efiDir = pkgs.runCommand "efi-directory" {
      nativeBuildInputs = [ pkgs.buildPackages.grub2_efi ];
      strictDeps = true;
    } ''
      mkdir -p $out/EFI/boot/
  
      # ALWAYS required modules.
  