webpack.config.js

const path = require('path');

module.exports = {
  entry: './src/index.ts',
  mode: 'production',
  devServer: {
    contentBase: path.join(__dirname, 'build'),
    compress: true,
    port: 3000,
  },
  module: {
    rules: [
      {
        test: /\.tsx?$/,
        use: 'ts-loader',
        exclude: /node_modules/,
      },
    ],
  },
  resolve: {
    extensions: ['.tsx', '.ts', '.js'],
    alias: {
      react: path.resolve(__dirname, './node_modules/react'),
      'react-dom': path.resolve(__dirname, './node_modules/react-dom'),
    },
  },
  externals: {
    // Don't bundle react or react-dom
    react: {
      commonjs: 'react',
      commonjs2: 'react',
      amd: 'React',
      root: 'React',
    },
    'react-dom': {
      commonjs: 'react-dom',
      commonjs2: 'react-dom',
      amd: 'ReactDOM',
      root: 'ReactDOM',
    },
  },
  output: {
    filename: 'index.js',
    path: path.resolve(__dirname, 'dist'),
    libraryTarget: 'umd',
    globalObject: 'this',
    publicPath: '/dist/',
    umdNamedDefine: true,
  },
};