text: const merge = require("webpack-merge");
  const UglifyJsPlugin = require('uglifyjs-webpack-plugin');
  const { CleanWebpackPlugin } = require('clean-webpack-plugin');
  const common = require('./webpack.common.js');
  
  var config = {
    mode : 'production',
    optimization : {
      minimize : true,
      splitChunks: {
        cacheGroups: {
          vendors: {
            test: /[\\/]node_modules[\\/]/,
            name: 'vendor',
            priority: -10,
            minSize: 0,
            reuseExistingChunk: true,
            chunks: 'initial',
            enforce: true,
          },
          utilities: {
            test: /[\\/]src[\\/]utils[\\/]/,
            name: 'utils',
            minSize: 0,
            reuseExistingChunk: true,
            chunks: 'all',
          },
        },
      }
    },
    plugins: [ 
      new UglifyJsPlugin(),
      new CleanWebpackPlugin({
        parallel : true,
        cache : true,
        sourceMap : true,
        uglifyOPtions : {
          output :{
            comments : false
          }
        }
      }
    )]
  };
  
  module.exports = merge(common, config);