gulpfile.js

function scripts(watch) {
  var bundler, rebundle;
  bundler = browserify('./src/client.js', {
    basedir: __dirname, 
    debug: !production, 
    cache: {}, // required for watchify
    packageCache: {}, // required for watchify
    fullPaths: watch // required to be true only for watchify
  });
  if(watch) {
    bundler = watchify(bundler) 
  }

  bundler.transform(reactify);

  rebundle = function() {
    var stream = bundler.bundle();
    stream.on('error', handleError('Browserify'));
    stream = stream.pipe(source('bundle.js'));
    return stream.pipe(gulp.dest('./assets/js'));
  };

  bundler.on('update', rebundle);
  return rebundle();
}