these 3 derivations will be built:
  /nix/store/9ygspympbfzl05r24k0ysd36l43bq6l3-docker-image-sources.drv
  /nix/store/j831nsrzi7y016pwi3ml2y8f197psc10-docker-image-inputs.drv
  /nix/store/k60arsdalmglyi209qjrm2x3vcgx59cr-docker-image-inputs-hash.drv