these 2 derivations will be built:
  /nix/store/lmwrf1vlgawr1y0gq3l2i6hvhwjdapd6-iets-0.1.0.drv
  /nix/store/xiwmajaj290ayvqn1v98yk6m5hg1i5kg-iets-langtests.drv