webpack.dev.js

const path = require('path');
const CompressionPlugin = require("compression-webpack-plugin");
const zlib = require('zlib');

module.exports = {
  mode: 'development',
  devtool: 'source-map',
  entry: path.join(__dirname, 'client', 'src', 'index.jsx'),
  output: {
    path: path.resolve(__dirname, 'client', 'dist'),
    filename: 'bundle.js',
  },
  resolve: {
    extensions: ['', '.js', '.jsx'],
  },
  module: {
    rules: [
      {
        test: /\.(js|jsx)?/,
        exclude: /node_modules/,
        use: {
          loader: 'babel-loader',
          options: {
            presets: ['@babel/preset-env', '@babel/preset-react'],
            plugins: ['babel-plugin-styled-components'],
          },
        },
      },
    ],
  },
  plugins: [
    new CompressionPlugin({
      filename: "[path][base].gz",
      algorithm: "gzip",
      test: /\.js$|\.css$|\.html$/,
      threshold: 10240,
      minRatio: 0.8,
    }),
    new CompressionPlugin({
      filename: "[path][base].br",
      algorithm: "brotliCompress",
      test: /\.(js|css|html|svg)$/,
      compressionOptions: {
        params: {
          [zlib.constants.BROTLI_PARAM_QUALITY]: 11,
        },
      },
      threshold: 10240,
      minRatio: 0.8,
    }),
  ],
};