webpack.config.js

const isDev = process.env.NODE_ENV === 'development'
const path = require('path')
const SRC = path.resolve(__dirname, 'node_modules')

module.exports = {
  mode: isDev ? 'development' : 'production',
  entry: [
    '@babel/polyfill', // enables async-await
    './client/index.js'
  ],
  output: {
    path: __dirname,
    filename: './public/bundle.js'
  },
  resolve: {
    extensions: ['.js', '.jsx']
  },
  devtool: 'source-map',
  watchOptions: {
    ignored: /node_modules/
  },
  module: {
    rules: [
      {
        test: /\.jsx?$/,
        exclude: /node_modules/,
        loader: 'babel-loader'
      },
      {
        test: /\.css$/i,
        use: ['style-loader', 'css-loader']
      },
      {
        test: /\.(png|jpg|gif|svg|jpe?g)$/i,
        use: [
          {
            loader: 'file-loader',
            options: {
              limit: 8192
            }
          }
        ]
      },
      {
        test: /\.mp3$/,
        include: SRC,
        loader: 'file-loader'
      }
    ]
  }
}