these 2 derivations will be built:
  /nix/store/g81q4z22przyqmlrw1vz0sphcxy22h4y-nixos-test-driver-wal2json.drv
  /nix/store/0hd5g7r1cqchvxkikbam8zzz5nn1gp6f-vm-test-run-wal2json.drv