these 3 derivations will be built:
  /nix/store/7rpampqyfrwfh64smdgg91489knwn5j3-serde_json-1.0.154.drv
  /nix/store/2rpk5a7ygwyqj2595scrybp5s8afv0dn-cargo-vendor-dir.drv
  /nix/store/qvndplwi3v3lz62h1cy6zbk1dm36sjav-bob-0.1.0.drv