qinsong77 / r19

A dead-simple React 19 "framework" implementation from scratch

R19 🏎️

A React 19 "framework" from scratch.

The name was definitely not inspired by F1 cars. :))

Features

This has a lot of cool caveats, like using Bun for most of the internals and (maybe) the first React 19 framework to implement ESM and not a bundler like Webpack to be bundled.

• Bundling
  • TS Support
    • JSX Support
  • Assets (Images, Styles, etc...)
• File-based routing
• RSC (React Server Components)
• RSA (React Server Actions)
• SSR
  • Static export
    • Serve static files for default route states

Examples

• Simple
  • A basic overview of the features
• Advanced
  • A more complex system with a SQLite database

Usage

This project uses react-server-dom-esm as the "plugin" to integrate with most of the React 19 features. But this package is not published yet, so you need to clone the react repo and build it yourself.

git clone https://github.com/facebook/react.git
cd react
yarn && yarn build

Then, the predev script will copy the necessary files to the node_modules folder. (It expects the react repo to be in the same parent directory as this repo.)

With all the dependencies set up, you can run the project with:

bun i
bun dev

License

I don't encourage anyone to use this project in production, not even close to it. This is just a fun project where all can learn more about React and its internals.