anchor.diff:        # Generate convenience wrappers for running the test driver
         # interactively with the specified network, and for starting the
         # VMs from the command line.
  -      driver = let warn = if skipLint then lib.warn "Linting is disabled!" else lib.id; in warn (runCommand testDriverName
  +      driver = testDriver:
  +        let
  +          warn = if skipLint then lib.warn "Linting is disabled!" else lib.id;
  +        in
  +        warn (runCommand testDriverName
           { buildInputs = [ makeWrapper];
             testScript = testScript';
             preferLocalBuild = true;
  
positive.code:         meta = (drv.meta or {}) // t.meta;
        };
  
        test = passMeta (runTests driver);
  
        nodeNames = builtins.attrNames nodes;
        invalidNodeNames = lib.filter
  
negative.code:         # TODO: copy user script part into this file (append)
  
          wrapProgram $out/bin/nixos-test-driver \
            --prefix PATH : "${lib.makeBinPath [ qemu_pkg vde2 netpbm coreutils ]}" \
        '';
    };
  
    testDriver = mkTestDriver qemu_test;
    testDriverInteractive = mkTestDriver qemu_kvm;
  
    # Run an automated test suite in the given virtual network.
    # `driver' is the script that runs the network.
  