webpack.config.js

const path = require('path');
const HtmlWebpackPlugin = require('html-webpack-plugin');

module.exports = (env, argv) => {
    const isProduction = argv.mode === 'production' || !argv.mode;

    return {
        entry: './src/main.js',
        output: {
            filename: 'bundle.js',
            path: path.resolve(__dirname, 'dist'),
            clean: true,
        },
        devServer: {
            static: path.resolve(__dirname, 'dist'),
            port: 8000,
        },
        plugins: [
            new HtmlWebpackPlugin({
                template: './index.html',
                filename: 'index.html',
                scriptLoading: 'defer',
            }),
        ],
        module: {
            rules: [
                {
                    test: /\.js$/,
                    exclude: /node_modules/,
                    use: {
                        loader: 'babel-loader',
                        options: {
                            presets: ['@babel/preset-env']
                        }
                    }
                }
            ]
        },
        optimization: isProduction ? {
            minimize: true,
        } : {},
        mode: isProduction ? 'production' : 'development'
    };
};