gulp + browserify

gulp+browserify.js

var browserify = require('browserify')
  , gulp = require('gulp')
  , gutil = require('gulp-util')
  , mocha = require('gulp-mocha')
  , source = require('vinyl-source-stream')
  , watchify = require('watchify');

var b = watchify(browserify({
  entries: ['./app/index.js'],
  debug: true
}));

function bundle() {
  return b.bundle()
    .on('error', gutil.log.bind(gutil, 'Browserify Error'))
    .pipe(source('app.js'))
    .pipe(gulp.dest('./dist'));
}

gulp.task('browserify', bundle);