these 2 derivations will be built:
  /nix/store/6ny5qa2plmnbd6gynh0s4y5k7yrfnsqr-hol-guard-3.6.0.drv
  /nix/store/xr0l6rpbimxdwsn0d4d0lx7sfl8njfhr-check-hol-guard.drv