Webpack Config file. Produciton

webpack.config.production.js

import path from 'path'
import webpack from 'webpack'
import autoprefixer from 'autoprefixer'
import ExtractTextPlugin from 'extract-text-webpack-plugin'
import HtmlWebpackPlugin from 'html-webpack-plugin'

const buildPath = path.join(__dirname, 'build')
const entry = path.join(__dirname, 'app', 'index.js')
module.exports = {
  // real source-map for production
  devtool: 'source-map',
  entry: [
    // sets up an ES6-ish environment with promise support
    'babel-polyfill',
    // the main application script
    entry
  ],
  output: {
    path: buildPath,
    filename: 'bundle.js'
  },
  resolve: {
    extensions: ['', '.js', '.jsx', '.css', '.scss', '.json', '.node', '.png']
  },
  module: {
    loaders: [
      {
        test: /\.jsx?$/,
        exclude: /(node_modules)/,
        loader: 'babel',
        query: {
          cacheDirectory: true,
          presets: ['es2015', 'stage-0', 'react']
        }
      },
      {
        test: /\.css$/,
        loader: ExtractTextPlugin.extract('style-loader', 'css-loader')
      },
      {
        test: /\.scss$/,
        loader: ExtractTextPlugin.extract('style-loader', 'css-loader?modules&importLoaders=1&localIdentName=[name]__[local]___[hash:base64:5]!postcss!sass!toolbox')

      },
      {
        test: /\.json$/,
        loader: 'json'
      },
      {
        test: /\.node$/,
        loader: 'node-loader'
      },
      {
        test: /\.(jpe?g|png|gif)$/,
        loaders: [
          'file?hash=sha512&digest=hex&name=[name]_[hash].[ext]',
          'image-webpack?bypassOnDebug&optimizationLevel=7&interlaced=false'
        ]
      },
      {
        test: /\.woff(2)?(\?v=[0-9]\.[0-9]\.[0-9])?$/,
        loader: 'url-loader?limit=10000&mimetype=application/font-woff'
      },
      {
        test: /\.(ttf|eot|svg)(\?v=[0-9]\.[0-9]\.[0-9])?$/,
        loader: 'file-loader'
      }
    ]
  },
  postcss: [autoprefixer],
  toolbox: { theme: 'theme.scss' },
  plugins: [
    new ExtractTextPlugin('style.css', { allChunk: true }),
    new HtmlWebpackPlugin({
      template: './app/index.html'
    }),
    new webpack.optimize.DedupePlugin(),
    new webpack.optimize.UglifyJsPlugin({
      minimize: true,
      compress: {
        warnings: false
      }
    }),
    new webpack.DefinePlugin({
      'process.env': {
        'NODE_ENV': JSON.stringify('production')
      }
    })
  ]
}