these 3 derivations will be built:
  /nix/store/3j2yg8lybisygj4qvk5nji1w2pf9sgs7-source.drv
  /nix/store/fqmzznmb6rj85a0wgljf2r9b0maih1wn-collie-1.24.0.drv
  /nix/store/c92alb4swx4nr0rjnwqgc6hdxk8v0yjh-check-collie.drv