these 2 derivations will be built:
  /nix/store/iwjwpssaz4kdna3mfmca8p34lddawp0l-nixos-test-driver-pgroonga.drv
  /nix/store/ak70ggfrzkidkhwp1g1gbmdbi3kc7l7k-vm-test-run-pgroonga.drv