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Out-of-Tree Platforms

React Native is not just for Android and iOS - there are community-supported projects that bring it to other platforms, such as:

• React Native Windows - React Native support for Microsoft's Universal Windows Platform (UWP) and the Windows Presentation Foundation (WPF)
• React Native DOM - An experimental, comprehensive port of React Native to the web. (Not to be confused with React Native Web, which has different goals)
• React Native Desktop - A project aiming to bring React Native to the Desktop with Qt's QML. A fork of React Native Ubuntu, which is no longer maintained.
• React Native macOS - An experimental React Native fork targeting macOS and Cocoa

Creating your own React Native platform

Right now the process of creating a React Native platform from scratch is not very well documented - one of the goals of the upcoming re-architecture (Fabric) is to make maintaining a platform easier.

Bundling

As of React Native 0.57 you can now register your React Native platform with React Native's JavaScript bundler, Metro. This means you can pass --platform example to react-native bundle, and it will look for JavaScript files with the .example.js suffix. To register your platform with RNPM, your module's name must start with a react-native- suffix. You must also have an entry in your package.json like this:

{
  "rnpm": {
    "haste": {
      "providesModuleNodeModules": ["react-native-example"],
      "platforms": ["example"]
    }
  }
}

"providesModuleNodeModules" is an array of modules that will get added to the Haste module search path, and "platforms" is an array of platform suffixes that will be added as valid platforms.