Webpack Hot Reload

index.html

<script src="/static/bundle.js"></script>

server.js

var webpack = require('webpack');
var WebpackDevServer = require('webpack-dev-server');
var config = require('./webpack.config');

new WebpackDevServer(webpack(config), {
  hot: true,
  colors: true,
  publicPath: config.output.publicPath,
  historyApiFallback: true,
}).listen(3000, 'localhost', function (err, result) {
  if (err) {
    return console.log(err);
  }

  console.log('Listening at http://localhost:3000/');
});

webpack.config.js

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

module.exports = {
  devtool: 'eval',
  entry: [
    'webpack-dev-server/client?http://localhost:3000',
    'webpack/hot/only-dev-server',
    './js/main.v2'
  ],
  output: {
    path: path.join(__dirname, 'dist'),
    filename: 'bundle.js',
    publicPath: '/static/'
  },
  plugins: [
    new webpack.HotModuleReplacementPlugin()
  ],
  module: {
    loaders: [{
      test: /\.js$/,
      loaders: ['babel'],
      exclude: /node_modules/
    },
    {
      test: /\.scss$/,
      loaders: ["style", "css", "sass"]
    }]
  }
};