these 2 derivations will be built:
  /nix/store/yix2k4gkf4qaxp7w3bpyrg6pili51c7q-nixos-test-driver-pgrouting.drv
  /nix/store/l2bgfvp0harfilwsvhqlcnb0hvx6a26s-vm-test-run-pgrouting.drv