webpack-config.js

var webpack = require('webpack')
  , path = require('path')
  , opts

opts = {
  debug: process.env.NODE_ENV !== 'production'
, devtool: 'source-map'
, bail: true
, node: {
    console: true
  , global: true
  , process: true
  , Buffer: true
  , __filename: 'mock'
  , __dirname: 'mock'
  , setImmediate: true
  , net: 'empty'
  , tls: 'empty'
  , dns: 'empty'
  }
, module: {
    loaders: [
      {
        test: /\.jsx?$/,
        exclude: /node_modules/,
        loader: 'babel', // 'babel-loader' is also a legal name to reference
        query: {
          presets: ['react', 'es2015'],
          cacheDirectory: path.join(__dirname, 'cache')
        }
      }
    ]
  }
}

if (process.env.NODE_ENV === 'production') {
  opts.plugins = [
    new webpack.optimize.UglifyJsPlugin({
      mangle: {
        except: ['$super', '$', 'exports', 'require']
      }
    })
  ]
}

module.exports = opts