these 2 derivations will be built:
  /nix/store/nyaph3ih74blynm66bj7r9bbvln4c0gk-lean-ctx-3.10.0-vendor.drv
  /nix/store/91ni988cnz2284brp7h4w2f3lnrgrx9b-lean-ctx-3.10.0.drv