webpack.config.js

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

module.exports = {
  context: __dirname,
  entry: "./frontend/event_listenr.jsx",
  output: {
    path: path.resolve(__dirname, 'app', 'assets', 'javascripts'),
    filename: "./bundle.js"
  },
  // to unleash efficient webpack production build, uncomment the following:
  plugins: [
    new webpack.DefinePlugin({
      'process.env': {
        NODE_ENV: JSON.stringify('production')
      }
    }),
    new webpack.optimize.UglifyJsPlugin()
  ],
  // uncomment until here
  module: {
    loaders: [
      {
        test: [/.jsx?$/, /.js?$/],
        exclude: /node_modules/,
        loader: 'babel-loader',
        query: {
          presets: ['env', 'react']
        }
      }
    ]
  },
  devtool: 'source-maps',
  resolve: {
    extensions: [".js", ".jsx", "*"]
  }
};