these 2 derivations will be built:
  /nix/store/c0knxrazwsd5jcxwxx1rz8nnrx6x5zzb-iets-0.1.0.drv
  /nix/store/qrk443jjjvn4kh1bcxqdwnsacba8p7rw-iets-diff-e2e.drv