text: 'use strict';
  
  const webpack = require('webpack');
  
  module.exports = function(config) {
    if (config.env !== 'production') {
      return null;
    }
  
    return new webpack.optimize.UglifyJsPlugin({
      sourceMap: true,
      mangle: { screw_ie8 : true },
      compress: {
        screw_ie8: true,
        warnings: false
      },
      comments: false
    });
  };
  