these 2 derivations will be built:
  /nix/store/v812g0awzqvxl96q9r2gxmj88a7bfa8v-iets-0.1.0.drv
  /nix/store/chlwdkv776zk5ypfzsh6c9176f4i1r0b-iets-langtests.drv