text: const webpack = require('webpack');
  const merge = require('webpack-merge');
  const UglifyJSPlugin = require('uglifyjs-webpack-plugin');
  const CleanWebpackPlugin = require('clean-webpack-plugin');
  
  const common = require('./webpack.config');
  
  module.exports = merge(common, {
    devtool: 'source-map',
    plugins: [
      new UglifyJSPlugin({
        sourceMap: true
      }),
      new webpack.DefinePlugin({
        'process.env.NODE_ENV': '"production"'
      }),
      new CleanWebpackPlugin(['./public/js/*.js', './public/js/*.map'], {'allowExternal': true})
    ],
  });