these 3 derivations will be built:
  /nix/store/jjzd9r24svl4755irpvg5jabn208p245-droid.drv
  /nix/store/h3wkz8n1yn6b1i3z9sqx95s2k65ak8jx-droid-1.9.1.drv
  /nix/store/72h9kf5x0yb3zwqc3hn4fxgbwcvvj8kg-check-droid.drv