ooo-app

Universal JavaScript applications are tough to setup. Either you buy into a framework like Next.js or react-server, fork a boilerplate, or set things up yourself. Aiming to fill this void, Razzle is a tool that abstracts all complex configuration needed for SSR into a single dependency--giving you the awesome developer experience of create-react-app, but then leaving the rest of your app's architectural decisions about frameworks, routing, and data fetching up to you. With this approach, Razzle not only works with React, but also Reason, Elm, Vue, Angular, and most importantly......whatever comes next.

Razzle comes with the "battery-pack included":

• 🔥 Universal Hot Module Replacement, so both the client and server update whenever you make edits. No annoying restarts necessary
• Comes with your favorite ES6 JavaScript goodies (through babel-preset-razzle)
• Comes with the same CSS setup as create-react-app
• Works with React, Preact, Elm, Reason-React, Inferno, and Rax as well as Angular and Vue if that's your thing
• Escape hatches for customization via .babelrc and razzle.config.js
• Jest test runner setup with sensible defaults via razzle test

Quick Start

npm install -g create-razzle-app

create-razzle-app my-app
cd my-app
npm start

Then open https://localhost:3000/ to see your app. Your console should look like this:

That's it. You don't need to worry about setting up multiple webpack configs or other build tools. Just start editing src/App.js and go!

Below is a list of commands you will probably find useful.

npm start or yarn start

Runs the project in development mode.
You can view your application at https://localhost:3000

The page will reload if you make edits.

npm run build or yarn build

Builds the app for production to the build folder.

The build is minified and the filenames include the hashes. Your app is ready to be deployed!

npm run start:prod or yarn start:prod

Runs the compiled app in production.

You can again view your application at https://localhost:3000

npm test or yarn test

Runs the test watcher (Jest) in an interactive mode. By default, runs tests related to files changed since the last commit.

npm start -- --inspect or yarn start -- --inspect

To debug the node server, you can use razzle start --inspect. This will start the node server and enable the inspector agent. For more information, see this.

npm start -- --inspect-brk or yarn start -- --inspect-brk

To debug the node server, you can use razzle start --inspect-brk. This will start the node server, enable the inspector agent and Break before user code starts. For more information, see this.

Table of Contents

• Customization
  • Extending Babel Config
  • Extending Webpack
  • Environment Variables
  • Adding Temporary Environment Variables In Your Shell
    • Windows (cmd.exe)
    • Linux, macOS (Bash)
  • Adding Environment Variables In .env
    • What other .env files are can be used?
• How Razzle works (the secret sauce)
• Inspiration
  • Author
• Contributors

Customization

Customizing Babel Config

Razzle comes with most of ES6 stuff you need. However, if you want to add your own babel transformations, just add a .babelrc file to the root of your project.

{
  "presets": [
    "razzle/babel", // NEEDED
    "stage-0"
   ],
   "plugins": [
     // additional plugins
   ]
}

A word of advice: the .babelrc file will replace the internal razzle babelrc template. You must include at the very minimum the default razzle/babel preset.

Extending Webpack

You can also extend the underlying webpack config. Create a file called razzle.config.js in your project's root.

// razzle.config.js

module.exports = {
  modify: (config, {target, dev}, webpack) => {
    // do something to config
  
    return config
  }
}

A word of advice: razzle.config.js is an escape hatch. However, since it's just JavaScript, you can and should publish your modify function to npm to make it reusable across your projects. For example, imagine you added some custom webpack loaders and published it as a package to npm as my-razzle-modifictions. You could then write your razzle.config.js like so:

// razzle.config.js
const modify = require('my-razzle-modifictions');

module.exports = {
  modify
}

Last but not least, if you find yourself needing a more customized setup, Razzle is very forkable. There is one webpack configuration factory that is 300 lines of code, and 4 scripts (build, start, test, and init). The paths setup is shamelessly taken from create-react-app, and the rest of the code related to logging.

Environment Variables

The environment variables are embedded during the build time. You can read them at runtime just because by default we export them with the webpack.DefinePlugin.

• process.env.RAZZLE_PUBLIC_DIR: Path to the public directory.
• process.env.RAZZLE_ASSETS_MANIFEST: Path to a file containing compiled asset outputs
• process.env.REACT_DEV_BUNDLE_PATH: Relative path to where React will be bundled during development. Unless you are modifying the output path of your webpack config, you can safely ignore this. This path is used by react-error-overlay and webpack to power up the fancy runtime error iframe. For example, if you are using common chunks and an extra entry to create a vendor bundle with stuff like react, react-dom, react-router, etc. called vendor.js, and you've changed webpack's output to [name].js in development, you'd want to set this environment variable to /static/js/vendor.js. If you do not make this change, nothing bad will happen, you will simply not get the cool error overlay when there are runtime errors. You'll just see them in the console. Note: This does not impact production bundling.
• process.env.VERBOSE: default is false, setting this to true will not clear the console when you make edits in development (useful for debugging).
• process.env.PORT: default is 3000, unless changed
• process.env.PORT_DEV: default is 3001, unless changed
• process.env.HOST: default is 0.0.0.0
• process.env.NODE_ENV: 'development' or 'production'
• process.env.BUILD_TARGET: either 'client' or 'server'
• process.env.PUBLIC_PATH: Only in used in razzle build. You can alter the webpack.config.output.publicPath of the client assets (bundle, css, and images). This is useful if you plan to serve your assets from a CDN. Make sure to include a trailing slash (e.g. PUBLIC_PATH=https://cdn.example.com/). If you are using React and altering the public path, make sure to also include the crossorigin attribute on your `