these 2 derivations will be built:
  /nix/store/7lgxdqsxs0pzg2bvngbmnl8kb04v5w2a-hol-guard-3.5.0.drv
  /nix/store/d9c355rrh71gd0bp2hbclq0k20w8aqxi-check-hol-guard.drv