webpack.config.js

var webpack = require('webpack');

var isProd = (process.env.NODE_ENV === 'production');

// Conditionally return a list of plugins to use based on the current environment.
// Repeat this pattern for any other config key (ie: loaders, etc).
function getPlugins() {
  var plugins = [];
  plugins.push(new webpack.EnvironmentPlugin(['NODE_ENV']));
  if (isProd) {
    plugins.push(new webpack.optimize.UglifyJsPlugin());
  }
  return plugins;
}

module.exports = {
  entry: [
    './src/index.js'
  ],
  output: {
    path: __dirname,
    publicPath: '/',
    filename: 'bundle.js'
  },
  plugins: getPlugins(),
  module: {
    preLoaders: [{
      test: /\.js$/,
      exclude: /node_modules/,
      loader: 'eslint-loader'
    }],
    loaders: [{
      exclude: /node_modules/,
      loader: 'babel',
      query: {
        presets: ['react', 'es2015', 'stage-1']
      }
    }]
  },
  resolve: {
    extensions: ['', '.js', '.jsx']
  },
  devServer: {
    historyApiFallback: true,
    contentBase: './'
  }
};