these 2 derivations will be built:
  /nix/store/0fw7l0wxpvcs5id8pfm8j2nqsyc6k9jq-iets-0.2.0.drv
  /nix/store/amqm3pm9gdbczcidmd75yd0f038mb1ny-iets-classic-2.34.9.drv