these 2 derivations will be built:
  /nix/store/cj8hj962a6bnnhkil1704f6bcp2fz8v7-iets-0.1.0.drv
  /nix/store/0g9c8rmlbj4j72bxb9c6aji6zgbc79fx-iets-diff-e2e.drv