these 2 derivations will be built:
  /nix/store/idggfh8lnx45rmzzhmnm1vw1vjzhzhnd-nixos-test-driver-wal2json.drv
  /nix/store/1k2fr89c26pcyvj9jmldyi4zy4xn8s56-vm-test-run-wal2json.drv