webpack.prod.js

const merge = require('webpack-merge');
const common = require('./webpack.common.js');

const TerserJSPlugin = require('terser-webpack-plugin');
const MiniCssExtractPlugin = require('mini-css-extract-plugin');
const OptimizeCSSAssetsPlugin = require('optimize-css-assets-webpack-plugin');
const {CleanWebpackPlugin} = require('clean-webpack-plugin')

module.exports = merge(common, {
  mode: 'production',
  devtool: 'source-map',
  optimization: {
    minimizer: [new TerserJSPlugin({}), new OptimizeCSSAssetsPlugin({})],
  },
  plugins: [
    new MiniCssExtractPlugin({
      filename: '[name].css',
      chunkFilename: '[id].css',
    }),
    new CleanWebpackPlugin()
  ],
  module: {
    rules: [
      {
        test: /\.css$/,
        use: [MiniCssExtractPlugin.loader, 'css-loader'],
      },
    ],
  },
  output : {
    filename : '[name].[hash].js'
},
});