There are two things you want to do preparing for a production build.

• Configure a script to run in your package.json file
• Create a production config OR use node environment variables to make necessary changes in your Webpack config file

Creating the script

We have already used package.json to create the npm run dev script. Now let us set up npm run deploy.

{
  "name": "my-project",
  "version": "0.0.0",
  "description": "My awesome project!",
  "main": "app/main.js",
  "scripts": {
    "dev": "webpack-dev-server --devtool eval --progress --colors --hot --content-base build",
    "deploy": "NODE_ENV=production webpack -p --config webpack.production.config.js"
  },
  "author": "",
  "license": "ISC",
  "devDependencies": {
    "webpack": "^1.4.13",
    "webpack-dev-server": "^1.6.6"
  },
  "dependencies": {}
}

As you can see we are just running webpack with the production argument and pointing to a different configuration file. We also use the environment variable "production" to allow our required modules to do their optimizations. Lets us create the config file now.

Creating the production config

So there really is not much difference in creating the dev and production versions of your webpack config. You basically point to a different output path and there are no workflow configurations or optimizations. What you also want to bring into this configuration is cache handling.

var path = require('path');
var config = {
  entry: path.resolve(__dirname, '../app/main.js')
  output: {
    path: path.resolve(__dirname, '../dist'),
    filename: 'bundle.js'
  },
  module: {
    loaders: [{
      test: /\.js$/,

      // There is not need to run the loader through
      // vendors
      exclude: [node_modules_dir],
      loader: 'babel'
    }]
  }
};

module.exports = config;

Doing the deploy

Run npm run deploy in the root of the project. Webpack will now run in production mode. It does some optimizations on its own, but also React JS will do its optimizations. Look into caching for even more production configuration.