these 2 derivations will be built:
  /nix/store/hjq6l9mky0qycpiq7zh2dmp6zv8s8972-nixos-test-driver-pg_net.drv
  /nix/store/xlqmf2l2k6yhlzmdww3z2yym17xc4v1k-vm-test-run-pg_net.drv