webpack.config.js

plugins: [
  // put all npm modules in the 'vendor' chunk
  // matches react modules too, but they'll be moved by the next entry
  new webpack.optimize.CommonsChunkPlugin({
    name: 'vendor',
    minChunks: (module) => npmModuleRegex.test(module.resource)
  }),
  // put all key react modules in 'react' chunk
  // they're ~140KB (~40KB gz) and don't change often
  new webpack.optimize.CommonsChunkPlugin({
    name: 'react',
    minChunks: (module) => reactModuleRegex.test(module.resource)
  }),
  new webpack.optimize.CommonsChunkPlugin({
    name: 'common',
    names: [ 'manifest' ] // manifest is the code require to load other chunks
  }),
  ...
]