these 3 derivations will be built:
  /nix/store/qpwhhll3ca6j2nkdq5fd746ky2x59mip-source.drv
  /nix/store/2kdnpyilqgvph1x2papnbrbp12y8vcjh-collie-1.21.1.drv
  /nix/store/4d9j7hcbccma71i9vfn2zzr4y1q8z2n3-check-collie.drv