webpack.prod.js

const {merge} = require('webpack-merge');
const common = require('./webpack.common');
const CompressionPlugin = require('compression-webpack-plugin');
const {CleanWebpackPlugin} = require('clean-webpack-plugin');
const UglifyJsPlugin = require('uglifyjs-webpack-plugin');
const CssMinimizerPlugin = require('css-minimizer-webpack-plugin');

module.exports = merge(common, {
  mode: 'production',
  module: {
    rules: [
      {
        test: /\.js$/,
        exclude: '/node_modules/',
        use: [
          {
            loader: 'babel-loader',
            options: {
              presets: ['@babel/preset-env'],
            },
          },
        ],
      },
    ],
  },
  plugins: [
    new CleanWebpackPlugin(),
    new CssMinimizerPlugin(),
    new CompressionPlugin({
      filename: '[path][base].gz',
      algorithm: 'gzip',
      test: /\.(js|css)$/,
    }),
  ],
  optimization: {
    minimizer: [
      new UglifyJsPlugin({
        parallel: true,
        uglifyOptions: {
          compress: false,
          ecma: 6,
          mangle: true,
        },
        sourceMap: true,
      }),
    ],
    splitChunks: {
      chunks: 'all',
      minSize: 20000,
      maxSize: 70000,
      minChunks: 1,
      maxAsyncRequests: 30,
      maxInitialRequests: 30,
      automaticNameDelimiter: '.',
      enforceSizeThreshold: 50000,
      cacheGroups: {
        styles: {
          minChunks: 2,
          test: /\.css$/,
          enforce: true,
        },
        defaultVendors: {
          test: /[\\/]node_modules[\\/]/,
          priority: -10,
        },
        default: {
          minChunks: 2,
          priority: -20,
          reuseExistingChunk: true,
        },
      },
    },

  },
});