these 2 derivations will be built:
  /nix/store/s1gdpb3qwlkbhbnsrhw8dg4iwlw8scqf-treehouse-3.1.4.drv
  /nix/store/wk233h3b7lj5p8fxp7f72qha1aik5qd3-check-treehouse.drv