Webpack config for improving performance of development mode. (https://github.com/erikras/react-redux-universal-hot-example/issues/616)

dll.config.js

require('babel-polyfill');

var fs = require('fs');
var path = require('path');
var webpack = require('webpack');
var assetsPath = path.resolve(__dirname, '../static/dist');
var host = (process.env.HOST || 'localhost');
var port = (+process.env.PORT + 1) || 3001;

var WebpackIsomorphicToolsPlugin = require('webpack-isomorphic-tools/plugin');
var webpackIsomorphicToolsPlugin = new WebpackIsomorphicToolsPlugin(require('./webpack-isomorphic-tools'));

var babelrc = fs.readFileSync('./.babelrc');
var babelrcObject = {};

try {
  babelrcObject = JSON.parse(babelrc);
} catch (err) {
  console.error('==>     ERROR: Error parsing your .babelrc.');
  console.error(err);
}


var babelrcObjectDevelopment = babelrcObject.env && babelrcObject.env.development || {};

var combinedPlugins = babelrcObject.plugins || [];
combinedPlugins = combinedPlugins.concat(babelrcObjectDevelopment.plugins);

var babelLoaderQuery = Object.assign({}, babelrcObjectDevelopment, babelrcObject, {plugins: combinedPlugins});
delete babelLoaderQuery.env;

babelLoaderQuery.plugins = babelLoaderQuery.plugins || [];
var reactTransform = null;
for (var i = 0; i < babelLoaderQuery.plugins.length; ++i) {
  var plugin = babelLoaderQuery.plugins[i];
  if (Array.isArray(plugin) && plugin[0] === 'react-transform') {
    reactTransform = plugin;
  }
}

if (!reactTransform) {
  reactTransform = ['react-transform', {transforms: []}];
  babelLoaderQuery.plugins.push(reactTransform);
}

if (!reactTransform[1] || !reactTransform[1].transforms) {
  reactTransform[1] = Object.assign({}, reactTransform[1], {transforms: []});
}

reactTransform[1].transforms.push({
  transform: 'react-transform-hmr',
  imports: ['react'],
  locals: ['module']
});

module.exports = {
  cache: true,
  devtool: 'inline-eval-cheap-source-map',
  context: path.resolve(__dirname, '..'),
  entry: {
    app_assets: ['./src/client.js'],
    'main': [
      'webpack-hot-middleware/client?path=http://' + host + ':' + port + '/__webpack_hmr',
      // 'bootstrap-sass!./src/theme/bootstrap.config.js',
      // 'bootstrap-sass!./src/theme/bootstrap.config.js',
      'react-widgets-webpack!./src/theme/react-widgets.config.js',
      './src/client.js'
    ],
    vendor: [
      'react',
      'react-dom'
    ]
  },
  output: {
    path: assetsPath,
    filename: '[name].dll.js',
    library: '[name]',
    chunkFilename: '[name]-[chunkhash].js',
    publicPath: 'http://' + host + ':' + (port - 1) + '/dist/'
  },
  module: {
    preLoaders: [
      {
        test: /\.js$/,
        loader: 'eslint',
        include: [__dirname, path.join(__dirname, '../components')],
        exclude: [path.join(__dirname, '../', 'node_modules')],
      },
    ],
    loaders: [
      { test: /\.jsx?$/, exclude: /node_modules/, loaders: ['babel?' + JSON.stringify(babelLoaderQuery), 'eslint-loader']},
      { test: /\.json$/, loader: 'json-loader' },
      { test: /\.less$/, loader: 'style!css?modules&importLoaders=2&sourceMap&localIdentName=[local]___[hash:base64:5]!autoprefixer?browsers=last 2 version!less?outputStyle=expanded&sourceMap' },
      { test: /\.scss$/, loader: 'style!css?modules&importLoaders=2&sourceMap&localIdentName=[local]___[hash:base64:5]!autoprefixer?browsers=last 2 version!sass?outputStyle=expanded&sourceMap' },
      { test: /\.css$/, loader: "style!css" },
      { test: /\.woff(\?v=\d+\.\d+\.\d+)?$/, loader: 'url?limit=10000&mimetype=application/font-woff' },
      { test: /\.woff2(\?v=\d+\.\d+\.\d+)?$/, loader: 'url?limit=10000&mimetype=application/font-woff' },
      { test: /\.ttf(\?v=\d+\.\d+\.\d+)?$/, loader: 'url?limit=10000&mimetype=application/octet-stream' },
      { test: /\.eot(\?v=\d+\.\d+\.\d+)?$/, loader: 'file' },
      { test: /\.svg(\?v=\d+\.\d+\.\d+)?$/, loader: 'url?limit=10000&mimetype=image/svg+xml' },
      { test: webpackIsomorphicToolsPlugin.regular_expression('images'), loader: 'url-loader?limit=10240' }
    ]
  },
  progress: true,
  resolve: {
    modulesDirectories: [
      'src',
      'node_modules'
    ],
    extensions: ['', '.json', '.js', '.jsx']
  },
  eslint: {
    emitWarning: true
  },
  plugins: [
    // hot reload
    new webpack.HotModuleReplacementPlugin(),
    new webpack.IgnorePlugin(/webpack-stats\.json$/),
    new webpack.DefinePlugin({
      __CLIENT__: true,
      __SERVER__: false,
      __DEVELOPMENT__: true,
      __DEVTOOLS__: true  // <-------- DISABLE redux-devtools HERE
    }),
    new webpack.DllPlugin({
      name: '[name]',
      path: path.join( assetsPath, '[name]-manifest.json' )
    })
  ]
};