these 2 derivations will be built:
  /nix/store/f2v2b4ffqc3zmw02fml95l3mwx55b2gy-iets-0.1.0.drv
  /nix/store/nkkwxlrwxf8ykx10g01hlsrzhl5qygq7-iets-diff-e2e.drv