• You must use React on Rails v11.0.7 or higher.

Install the Gem and the Node Module

See Installation.

Setup Node Renderer Server

node-renderer is a standalone Node application to serve React SSR requests from a Rails client. You don't need any Ruby code to setup and launch it. You can configure with the command line or with a launch file.

Simple Command Line for node-renderer

  1. ENV values for the default config are (See JS Configuration for more details):
  2. Configure ENV values and run the command. Note, you can set port with args -p <PORT>. For example, assuming node-renderer is in your path:
    RENDERER_BUNDLE_PATH=/app/.node-renderer-bundles node-renderer
  3. You can use a command line argument of -p SOME_PORT to override any ENV value for the PORT.

JavaScript Configuration File

For the most control over the setup, create a JavaScript file to start the NodeRenderer.

  1. Create some project directory, let's say renderer-app:

    mkdir renderer-app
    cd renderer-app
  2. Make sure you have Node.js version 14 or higher and Yarn installed.

  3. Init node application and yarn add to install @shakacode-tools/react-on-rails-pro-node-renderer package.

    yarn init
    yarn add https://[your-github-token]:[email protected]/shakacode/react_on_rails_pro.git\#master
  4. Configure a JavaScript file that will launch the rendering server per the docs in Node Renderer JavaScript Configuration. For example, create a file node-renderer.js. Here is a simple example that uses all the defaults except for bundlePath:

    import path from 'path';
    import reactOnRailsProNodeRenderer from '@shakacode-tools/react-on-rails-pro-node-renderer';
    const config = {
      bundlePath: path.resolve(__dirname, '../.node-renderer-bundles'),
  5. Now you can launch your renderer server with node node-renderer.js. You will probably add a script to your package.json.

  6. You can use a command line argument of -p SOME_PORT to override any configured or ENV value for the port.

Setup Rails Application

Create config/initializers/react_on_rails_pro.rb and configure the renderer server. See configuration values in Configuration. Pay attention to:

  1. Set config.server_renderer = "NodeRenderer"
  2. Leave the default of config.prerender_caching = true and ensure your Rails cache is properly configured to handle the additional cache load.
  3. Configure values beginning with renderer_
  4. Use ENV values for values like renderer_url so that your deployed server is properly configured. If the ENV value is unset, the default for the renderer_url is localhost:3800.
  5. Here's a tiny example using mostly defaults:
ReactOnRailsPro.configure do |config|
 config.server_renderer = "NodeRenderer"
 # when this ENV value is not defined, the local server at localhost:3800 is used 
 config.renderer_url = ENV["REACT_RENDERER_URL"] 



The NodeRenderer has a protocol version on both the Rails and Node sides. If the Rails server sends a protocol version that does not match the Node side, an error is returned. Ideally, you want to keep both the Rails and Node sides at the same version.