these 3 derivations will be built:
  /nix/store/bgdxkk6gq1nz952iqcd5s9hj628gmvgb-docker-image-sources.drv
  /nix/store/ky4jjam5qqnps9qiy27nk4lmvsf7jm1b-docker-image-inputs.drv
  /nix/store/6hnsswxdfdypwmgrvkm7gic7w3sjdhwp-docker-image-inputs-hash.drv