Working gulp task that transpiles and bundles the application using Babel 6.0, ES2015 preset and Browserify

Gulp + Browserify + Babelify build with ES2015 modules

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


/*
  Transpiles the code using babel and es2015 preset and then bundles 
  the application in a file.
*/
gulp.task('bundle', function() {

  var bundler = browserify('./app/main.js', { debug: true })
                  .transform(babel.configure({
                    presets: ["es2015"]
                  }));

  bundler.bundle()
      .on('error', function(err) { console.error(err); this.emit('end'); })
      .pipe(source('build.js'))
      .pipe(buffer())
      .pipe(gulp.dest('./dist/js'));

});