these 3 derivations will be built:
  /nix/store/hdpskk10cc8ikxli4mmk9dhg47kf21vv-source.drv
  /nix/store/69rylh8xy3wpzqpkf316f10g15aza1n2-mcptoon-0.8.36.drv
  /nix/store/n2pzdxsfnaq2gyp0fdhdnycz7h51awa5-check-mcptoon.drv