these 3 derivations will be built:
  /nix/store/9xb2yrlfv215kz7k3vyjygg0das8fsmq-source.drv
  /nix/store/sdaq7xp540kf7ba3fwq2k58435wbcz92-collie-1.26.3.drv
  /nix/store/7avn9n54cvaqbxv9g7nb5vlmyb01rb71-check-collie.drv