these 3 derivations will be built:
  /nix/store/kp46rz0f4cgg562g48v3xhymlj9r0p17-source.drv
  /nix/store/5rmf8s9j659prqkrwlcxz1m5bcgy8kzh-collie-1.28.3.drv
  /nix/store/jsf8dhlliw5gzr529vy2v98zmcbdcvvz-check-collie.drv