these 2 derivations will be built:
  /nix/store/ignxjmq8328daw61pam3jsw6r4l4b2xp-openfang-0.6.9-vendor.drv
  /nix/store/9nzpdr35mcv0xv2w4hahazjq2zakld95-openfang-0.6.9.drv