webpack.config.js

var webpack  = require('webpack');
const path = require('path');

module.exports = {
  entry: './src/index.js',
  output: {
    path: path.resolve(__dirname,'dist'), // This is where images AND js will go
    publicPath: '', // This is used to generate URLs to e.g. images
    filename: 'react-selectable.js',
    libraryTarget: 'umd'
  },
  externals: {
    'react': {
		root: 'React',
		commonjs2: 'react',
		commonjs: 'react',
		amd: 'react',
    },
    'react-dom': {
		root: 'ReactDOM',
		commonjs2: 'react-dom',
		commonjs: 'react-dom',
		amd: 'react-dom'
  	}
  },
  module: {
    rules: [
      {
        test: /\.js$/,
        loader: 'babel-loader'
      }
    ]
  },
  resolve: {
      modules: ["node_modules"],
  },
  plugins: process.env.NODE_ENV === 'production' ? [
    new webpack.optimize.ModuleConcatenationPlugin(),
    new webpack.optimize.UglifyJsPlugin({
      compress: {
        warnings: false,
        screw_ie8: true,
        conditionals: true,
        unused: true,
        comparisons: true,
        sequences: true,
        dead_code: true,
        evaluate: true,
        if_return: true,
        join_vars: true
      },
      output: {
        comments: false
      }
    }),
  ] : []
};