webpack.production.config.js

// Webpack build script for production

const webpack = require('webpack');
const path = require('path');
const CopyWebpackPlugin = require('copy-webpack-plugin');

const uglifyJsPlugin = webpack.optimize.UglifyJsPlugin;

module.exports = {
  entry: [
    path.resolve(__dirname, 'src/index.js')
  ],
  output: {
    path: path.resolve(__dirname, 'dist'),
    publicPath: '/',
    filename: './bundle.js'
  },
  module: {
    loaders: [
      { test: /\.css$/, include: path.resolve(__dirname, 'src'), loader: 'style-loader!css-loader' },
      { test: /\.js[x]?$/, include: path.resolve(__dirname, 'src'), exclude: /node_modules/, loader: 'babel-loader' }
    ]
  },
  resolve: {
    extensions: ['', '.js', '.jsx']
  },
  plugins: [
    new webpack.optimize.DedupePlugin(),
    new uglifyJsPlugin({
      compress: {
        warnings: false
      }
    }),
    new webpack.DefinePlugin({
      'process.env': {
        NODE_ENV: JSON.stringify('production')
      }
    }),
    new CopyWebpackPlugin([
      { from: './src/index.html', to: 'index.html' },
    ])
  ]
};