gistfile1.txt

mbp:~/Sandbox/test% npm version
{ npm: '2.6.0',
  http_parser: '2.3',
  modules: '14',
  node: '0.12.0',
  openssl: '1.0.1l',
  uv: '1.0.2',
  v8: '3.28.73',
  zlib: '1.2.8' }
mbp:~/Sandbox/test% gulp watchify
[14:15:07] Using gulpfile ~/Sandbox/test/gulpfile.js
[14:15:07] Starting 'watchify'...
^C
gulp watchify  38.60s user 5.12s system 103% cpu 42.088 total

watchify.js

'use strict';

var gulp = require('gulp');
var browserify = require('browserify');
var watchify = require('watchify');
var source = require('vinyl-source-stream');
var babelify = require('babelify');

module.exports = gulp.task('watchify', function () {
  var bundler = browserify({
    cache: {},
    packageCache: {},
    fullPaths: true,
    entries: [config.paths.src.js],
    debug: true,
    extensions: ['.js']
  });

  bundler = watchify(bundler);
  bundler.transform(babelify);

  function rebundle() {
    return bundler.bundle()
    .pipe(source(config.filenames.build.scripts))
    .pipe(gulp.dest(config.paths.dest.build.scripts));
  }

  bundler.on('update', rebundle);

  return rebundle();
});