these 3 derivations will be built:
  /nix/store/774ibjqqs6plih5nn9dlpcqny41rpfvi-hol_guard-3.18.2.tar.gz.drv
  /nix/store/mv273nwjr0aq71brww9m7wib1kipsv4p-hol-guard-3.18.2.drv
  /nix/store/hg4naa2srlxkwr5pnmdfvg2r2m7jc5g6-check-hol-guard.drv