these 3 derivations will be built:
  /nix/store/dbzs37wy4rpxpiq0pavwa5j9y1r5pn56-source.drv
  /nix/store/20v1r5y3hfbqvixs067vydy0vm0kmhp3-mcptoon-0.8.2.drv
  /nix/store/lqddlhi3x7y7gifx3gq5vcr8q7jbxgvs-check-mcptoon.drv