const merge = require('webpack-merge') const TerserPlugin = require('terser-webpack-plugin') const OptimizeCssAssetsPlugin = require('optimize-css-assets-webpack-plugin') const MiniCssExtractPlugin = require('mini-css-extract-plugin') const base = require('./webpack.config') // Use "smart" merge: attempts to combine loaders targeting the same file type, // overriding the base config module.exports = merge.smart( base, { mode: 'production', // Enable a full source map. Generates a comment linking to the source map devtool: 'hidden-source-map', output: { // Override filename to include hash for immutable caching filename: 'js/[name]-[chunkhash].js', }, module: { rules: [ { // Override base font loading to add hash to filename so that we can // use "immutable" caching test: /\.(woff|woff2)$/, use: [ { loader: 'file-loader', options: { outputPath: 'fonts', publicPath: '/fonts/', name: '[name]-[hash]-1.[ext]', }, }, ], }, ], }, optimization: { // Minify JS (with Terser) and CSS (with cssnano) minimizer: [ new TerserPlugin({ terserOptions: { keep_classnames: /Error$/, keep_fnames: /Error$/, }, }), new OptimizeCssAssetsPlugin(), ], }, plugins: [ // Extract CSS to a separate file (rather than inlining to a