these 3 derivations will be built:
  /nix/store/q8n039s3r5awm9z2lv75yps53fnak7p1-hol_guard-3.12.0.tar.gz.drv
  /nix/store/9xjc3hl1pli5abvj6gm5vwcj9m5yr11c-hol-guard-3.12.0.drv
  /nix/store/ns0g0xqggwy0jlhvjh38lrq17hj0xm66-check-hol-guard.drv