webpack.prod.js

const { merge } = require('webpack-merge');
const { CleanWebpackPlugin } = require('clean-webpack-plugin');
const { BundleAnalyzerPlugin } = require('webpack-bundle-analyzer');
const common = require('./webpack.common');

module.exports = merge(common, {
    mode: 'production',
    optimization: {
        splitChunks: {
            chunks: 'all',
            minSize: 20000,
            maxSize: 70000,
            minChunks: 1,
            maxAsyncRequests: 30,
            maxInitialRequests: 30,
            automaticNameDelimiter: '~',
            cacheGroups: {
                defaultVendors: {
                    test: /[\\/]node_modules[\\/]/,
                    priority: -10,
                },
                default: {
                    minChunks: 2,
                    priority: -20,
                    reuseExistingChunk: true,
                },
            },
        },
    },
    module: {
        rules: [
            {
                test: /\.js$/,
                exclude: '/node_modules/',
                use: [
                    {
                        loader: 'babel-loader',
                        options: {
                            presets: ['@babel/preset-env'],
                        },
                    },
                ],
            },
        ],
    },
    plugins: [
        new CleanWebpackPlugin(),
        new BundleAnalyzerPlugin(),
    ],
});