webpack.prod.js

const merge = require('webpack-merge');

const TerserPlugin = require('terser-webpack-plugin');
const ImageminPlugin = require('imagemin-webpack-plugin').default;
const imageminMozjpeg = require('imagemin-mozjpeg');
const CompressionPlugin = require('compression-webpack-plugin');

const FaviconsWebpackPlugin = require('favicons-webpack-plugin');
const OfflinePlugin = require('offline-plugin');

const UglifyJsPlugin = require("uglifyjs-webpack-plugin");
const OptimizeCSSAssetsPlugin = require("optimize-css-assets-webpack-plugin");
const MiniCssExtractPlugin = require("mini-css-extract-plugin");

const common = require("./webpack.common.js");

module.exports = merge(common, {
  mode: "production",

  output: {
    filename: "[name].[hash:5].js",
    chunkFilename: "[id].[hash:5].css"
  },

  optimization: {
    minimizer: [
      new TerserPlugin({
        cache: true,
        parallel: true,
        sourceMap: true,
        exclude: /\/node_modules\//,
      }),
      new MiniCssExtractPlugin({
        filename: "[name].[hash:5].css",
        chunkFilename: "[id].[hash:5].css"
      }),

      new OptimizeCSSAssetsPlugin({})
    ]
  },

  plugins: [
    new ImageminPlugin({
      test: /\.(jpe?g|png|gif|svg)$/i,
      gifsicle: { // lossless gif compressor
        optimizationLevel: 9
      },
      pngquant: ({ // lossy png compressor, remove for default lossless
        quality: '75'
      }),
      plugins: [imageminMozjpeg({ // lossy jpg compressor, remove for default lossless
        quality: '75'
      })]
    })
  ]
});