code: function addHooks () {
      browserify.pipeline.get('pack').push(through(function write (row, enc, next) {
        next(null, row);
      }, function end (cb) {
        // on each bundle, create a new stream b/c the old one might have ended
        var compiledCssStream = new ReadableStream();
        compiledCssStream._read = function () {};
  
        browserify.emit('css stream', compiledCssStream);
  
        // Combine the collected sources for a single bundle into a single CSS file
        var self = this;
        var css = loader.finalSource;
  
        // end the output stream
        compiledCssStream.push(css);
        compiledCssStream.push(null);
  
        var writes = [];
  
        // write the css file
        if (cssOutFilename) {
          writes.push(writeFile(cssOutFilename, css));
        }
  
        // write the classname manifest
        if (jsonOutFilename) {
          writes.push(writeFile(jsonOutFilename, JSON.stringify(normalizeManifestPaths(tokensByFile, rootDir))));
        }
        Promise.all(writes)
          .then(function () { cb(); })
          .catch(function (err) { self.emit('error', err); cb(); });
      }));
    }
docs: ----