these 2 derivations will be built:
  /nix/store/86hj12nmgx5r5sh9l5qdh5m8f4cvsryn-nixos-test-driver-pgroonga.drv
  /nix/store/0hrpijswfzwkwfakcayrkls9fahbkcj6-vm-test-run-pgroonga.drv