these 3 derivations will be built:
  /nix/store/zz85q7fk89wy4syj9jfsfwj7vhm23r6p-docker-image-sources.drv
  /nix/store/r1a2hka3fv7zgxil1i1b5vz82i96cyl7-docker-image-inputs.drv
  /nix/store/8rb0cvx0i80p9kp92y44fwicnmp1rk82-docker-image-inputs-hash.drv