these 5 derivations will be built:
  /nix/store/0g9v2818g3i4xi9ri6cfx65lmbghr478-efi-directory.drv
  /nix/store/0fh9kimclai9r40jwgc695wv1zrw9wbv-efi-image_eltorito.drv
  /nix/store/aqq3ip7qkhbsldabj1wd2fv257wyhnlj-closure-info.drv
  /nix/store/qn12kilczhim30n4bl8zhbjamg7j6b0c-isolinux.cfg.drv
  /nix/store/8vfkihvjhr5a8f3c8kf5vak5k85d6zp0-spaces-os.iso.drv