text: const webpack = require('webpack');
  const HtmlWebpackPlugin = require('html-webpack-plugin');
  
  module.exports = {
    mode: 'development',
  
    entry: {
      app: './app.js'
    },
  
    devtool: 'source-map',
  
    module: {
      rules: [
        {
          // Compile ES2015 using babel
          test: /\.js$/,
          exclude: [/node_modules/],
          use: [
            {
              loader: 'babel-loader',
              options: {
                presets: ['@babel/env', '@babel/react']
              }
            }
          ]
        }
      ]
    },
  
    // Optional: Enables reading mapbox token from environment variable
    plugins: [
      new HtmlWebpackPlugin({title: 'react-map-gl Example'}),
      new webpack.EnvironmentPlugin(['MapboxAccessToken'])
    ]
  };
  