these 2 derivations will be built:
  /nix/store/zf72ln9x2xwj685q4bpb0d4fdq9kfzyi-hol-guard-3.9.0.drv
  /nix/store/6al6ch1kzmjapwsvpq2i0lippgpycgk1-check-hol-guard.drv