these 2 derivations will be built:
  /nix/store/gq120k0hlmjxnb1ddmmd22rh2rjaxpa5-iets-0.1.0.drv
  /nix/store/h7ar3nk6f1ahnhm7g61m5jjmwggn5a5s-iets-langtests.drv