Local libraries setup

A local library is a library containing views or modules that's local to your app and not published to a registry. This is different from the traditional setup for view and modules in the sense that a local library is decoupled from your app's native code.

The local library is created outside of the android/ and ios/ folders and makes use of autolinking to integrate with your app. The structure with a local library may look like this:

MyApp
├── node_modules
├── modules <-- folder for your local libraries
│ └── awesome-module <-- your local library
├── android
├── ios
├── src
├── index.js
└── package.json

Since a local library's code exists outside of android/ and ios/ folders, it makes it easier to upgrade React Native versions in the future, copy to other projects etc.

To create local library we will use create-react-native-library. This tool contains all the necessary templates.

Getting Started

Inside your React Native application's root folder, run the following command:

npx create-react-native-library@latest awesome-module

Where awesome-module is the name you would like for the new module. After going through the prompts, you will have a new folder called modules in your project's root directory which contains the new module.

Linking

By default, the generated library is automatically linked to the project using link: protocol when using Yarn and file: when using npm:

npm

"dependencies": {
  "awesome-module": "file:./modules/awesome-module"
}

Yarn

"dependencies": {
  "awesome-module": "link:./modules/awesome-module"
}

This creates a symlink to the library under node_modules which makes autolinking work.

Installing dependencies

To link the module you need to install dependencies:

npm

npm install

Yarn

yarn install

Using module inside your app

To use the module inside your app, you can import it by its name:

import {multiply} from 'awesome-module';