these 2 derivations will be built:
  /nix/store/zj9z20amrz35gcqv5w4frqsmbkcglgri-iets-0.1.0.drv
  /nix/store/gcwsikd8w6lm8zgysx9rjj2wmzc2w7zq-iets-diff-e2e.drv