anchor.diff:          testName = name;
           qemu_pkg = pkgs.qemu;
           nodes = nodes pkgs.qemu;
  +        interactive = true;
         };
   
         test =
  
positive.code:     , enableOCR ? false
      , skipLint ? false
      , passthru ? {}
    }:
      let
        # Reifies and correctly wraps the python test driver for
  
negative.code:         wrapProgram $out/bin/nixos-test-driver \
            --set startScripts "''${vmStartScripts[*]}" \
            --set testScript "$out/test-script" \
            --set vlans '${toString vlans}' \
            ${if interactive then "--add-flags --interactive" else ""}
        '');
  
    # Make a full-blown test
  