these 2 derivations will be built:
  /nix/store/knmp55kmr4qkjlxcnhsk2xknvzl26w8r-mardi-gras-0.36.0.drv
  /nix/store/im6zypvrzwgw0q2nays3kv8n5g2ky3l9-check-mardi-gras.drv