these 2 derivations will be built:
  /nix/store/7rshjdh9fb3hsrsr9y8200vij5frlpz9-nixos-test-driver-pg_repack.drv
  /nix/store/rgdldk8hic4x0lrvclhi3fsbgs1w9g6i-vm-test-run-pg_repack.drv