these 2 derivations will be built:
  /nix/store/7zvq61cpj4cy9017qaxx9cjs02i69bbc-mac-4.11.4.5.7-output.patch.drv
  /nix/store/saal565g6dzhbh074mrwvalzb707vgh5-mac-4.11-u4-b5-s7.drv