webpack.config.js

const webpack = require('webpack')
const path = require('path')

var ExtractTextPlugin = require('extract-text-webpack-plugin');
var BUILD_DIR = path.resolve(__dirname, 'src/public');
var APP_DIR = path.resolve(__dirname, 'src/app');

module.exports = {
    devtool: 'source-map',
    entry: {
        'app': [
            'babel-polyfill',
            'react-hot-loader/patch',
            './src/app/index.jsx'
        ]
    },
    output: {
        path: BUILD_DIR,
        publicPath: '/public/',
        filename: 'bundle.js'
    },
    module: {
        loaders : [
            {
                test : /\.jsx?/,
                include : APP_DIR,
                loader : 'babel-loader'
            },
            {
                test: /\.scss$/,
                loader: ExtractTextPlugin.extract('css-loader!sass-loader')
            }
        ]
    },
    plugins: [
        new ExtractTextPlugin({
            filename: BUILD_DIR + '/bundle.css',
            allChunks: true
        })
    ]
}

package.json

{
  "name": "( ͡° ͜ʖ ͡°)",
  "version": "1.0.0",
  "description": "",
  "main": "src/app/index.js",
  "scripts": {
    "bundle": "webpack -d",
    "server": "webpack-dev-server --hot --content-base src/ --history-api-fallback --open"
  },
  "author": "( ͡° ͜ʖ ͡°)",
  "license": "MIT",
  "devDependencies": {
    "babel-core": "^6.24.1",
    "babel-loader": "^6.4.1",
    "babel-polyfill": "^6.23.0",
    "babel-preset-latest": "^6.24.1",
    "babel-preset-react": "^6.24.1",
    "css-loader": "^0.28.0",
    "extract-text-webpack-plugin": "^2.1.0",
    "node-sass": "^4.5.2",
    "react-hot-loader": "^3.0.0-beta.6",
    "sass-loader": "^6.0.3",
    "style-loader": "^0.16.1",
    "webpack": "^2.3.3",
    "webpack-dev-server": "^2.4.2"
  },
  "dependencies": {
    "react": "^15.5.4",
    "react-dom": "^15.5.4"
  }
}