these 3 derivations will be built:
  /nix/store/4fl13hp09qps3x539vvsfc3xgxxda7mz-source.drv
  /nix/store/r3c4r0dqvs00zdbrm902hk83qkl9dn8s-herdr-eternal-deps-0.1.0.drv
  /nix/store/hiikia270lq5ysqrg991kcrinhrl5aiw-herdr-eternal-test-0.1.0.drv