Gulp + Babel

gistfile1.txt

/**
* Generic Gulpfile for building small AngularJS modules. This does the *very minimum*
* amount of work to get a module to build.
* npm install --save-dev gulp gulp-concat gulp-uglify del babel babel-preset-es2015 gulp-babel
*/
var gulp = require('gulp');
var concat = require('gulp-concat');
var uglify = require('gulp-uglify');
var config = require('./package.json');
var del = require('del');
var babel = require('gulp-babel');

// configure for your source files
var src = ['./src/**/*.module.js', './src/**/*.js', '!./src/**/*.spec.js'];

// reads the name of the module distributable from package.json
var match = config.main.match(/(.*)[/](.*)/);
var path = match[1];
var file = match[2];

gulp.task('clean', function () {
  return del(path);
});

gulp.task('build', ['clean'], function () {
  gulp
      .src(src)
      .pipe(babel({ presets: ['es2015']}))
      .pipe(concat(file))
      .pipe(uglify())
      .pipe(gulp.dest(path));
});