webpack.config.js

const path = require("path");

module.exports = {
  mode: "development",
  entry: "./src/index.tsx",
  output: {
    filename: "index.js",
    path: __dirname + "/lib",
    library: "qljs",
    libraryTarget: "umd"
  },

  // Enable sourcemaps for debugging webpack's output.
  devtool: "source-map",

  resolve: {
    extensions: [".ts", ".tsx", ".js", ".json"]
  },

  module: {
    rules: [
      // All files with a '.ts' or '.tsx' extension will be handled by 'awesome-typescript-loader'.
      { test: /\.tsx?$/, loader: "awesome-typescript-loader" },

      // All output '.js' files will have any sourcemaps re-processed by 'source-map-loader'.
      { enforce: "pre", test: /\.js$/, loader: "source-map-loader" }
    ]
  },

  // When importing a module whose path matches one of the following, just
  // assume a corresponding global variable exists and use that instead.
  // This is important because it allows us to avoid bundling all of our
  // dependencies, which allows browsers to cache those libraries between builds.
  externals: {
    react: {
      root: "React",
      commonjs2: "react",
      commonjs: "react",
      amd: "react",
      umd: "react"
    },
    "react-dom": {
      root: "ReactDOM",
      commonjs2: "react-dom",
      commonjs: "react-dom",
      amd: "react-dom",
      umd: "react-dom"
    }
  }
};