webpack.config.js

const { resolve } = require('path');
const webpack = require('webpack');
const ExtractTextPlugin = require('extract-text-webpack-plugin');

module.exports = {
  context: resolve(__dirname, 'src'),
  entry: [
    './index.js',
    // the entry point of our app
  ],
  output: {
    filename: 'dist/bundle.js',
  },
  devtool: 'source-map',
  module: {
    rules: [
      {
        test: /\.jsx?$/,
        use: ['babel-loader'],
        exclude: /node_modules/,
      },
      {
        test: /\.scss$/,
        use: ['css-hot-loader'].concat(ExtractTextPlugin.extract({
          use: [
            {
              loader: 'css-loader', // translates CSS into CommonJS
            },
            {
              loader: 'sass-loader', // compiles Sass to CSS
            },
          ],
          fallback: 'style-loader', // used when css not extracted
        })),
      },
      {
        test: /\.woff($|\?)|\.woff2($|\?)|\.ttf($|\?)|\.eot($|\?)|\.svg($|\?)/,
        use: 'url-loader',
      },
    ],
  },
  externals: {
    'react/addons': true,
    'react/lib/ExecutionEnvironment': true,
    'react/lib/ReactContext': true,
  },
  plugins: [
    new webpack.NamedModulesPlugin(),
    // prints more readable module names in the browser console on HMR updates

    new ExtractTextPlugin({ filename: 'styles.css', allChunks: true }),
  ],
};