these 2 derivations will be built:
  /nix/store/vqi198p5qdk3nv8wiwqivdwsqisv3x3q-cargo-vendor-dir.drv
  /nix/store/i3c4sr4lkn08innzgdcz1w5fqslcr9z2-ssync-0.5.0.drv