these 2 derivations will be built:
  /nix/store/vx9dr1lv7j9vaa6s1gki38j20ccmg32j-nixos-test-driver-postgis.drv
  /nix/store/1kym5cs29kd6yyc9i2kmnsv94mmvk2x9-vm-test-run-postgis.drv