these 3 derivations will be built:
  /nix/store/9q69h6v41rj91b4vdz61g9m18fir36aw-source.drv
  /nix/store/wdnkjg5x85068hq08rzzxhaybpjdlr3q-collie-1.23.3.drv
  /nix/store/6llsc5xrs42m9c35l6xs287hbfiaadaf-check-collie.drv