these 3 derivations will be built:
  /nix/store/0rqybk1gxyabsdsp98sx0ak6vkyakkjv-docker-image-sources.drv
  /nix/store/y5dyf0f9aiidaa0rshilm6i8j4k1fq0b-docker-image-inputs.drv
  /nix/store/z1d4zz2mhgl8rnxllsw406kqacfxvkdz-docker-image-inputs-hash.drv