https://github.com/react-native-community/javascriptcore
JavaScriptCore for React Native
https://github.com/react-native-community/javascriptcore
Last synced: 8 months ago
JSON representation
JavaScriptCore for React Native
- Host: GitHub
- URL: https://github.com/react-native-community/javascriptcore
- Owner: react-native-community
- License: mit
- Created: 2025-02-06T11:06:07.000Z (about 1 year ago)
- Default Branch: main
- Last Pushed: 2025-05-07T15:40:59.000Z (9 months ago)
- Last Synced: 2025-06-21T21:55:36.240Z (8 months ago)
- Language: C++
- Size: 397 KB
- Stars: 48
- Watchers: 10
- Forks: 5
- Open Issues: 2
-
Metadata Files:
- Readme: README.md
- License: LICENSE
Awesome Lists containing this project
README
# React Native JavaScriptCore
Opt-in to use JavaScriptCore runtime in React Native.
_Note: JavaScriptCore has been extracted from core react-native as a part of [Lean Core JSC RFC](https://github.com/react-native-community/discussions-and-proposals/blob/main/proposals/0836-lean-core-jsc.md)([PR](https://github.com/react-native-community/discussions-and-proposals/pull/836))._
## Installation
> [!IMPORTANT]
> This library only supports React Native 0.79 and above with new architecture enabled.
```sh
yarn add @react-native-community/javascriptcore
```
### iOS
Install pods:
```sh
cd ios && USE_THIRD_PARTY_JSC=1 USE_HERMES=0 bundle exec pod install
```
> [!NOTE]
> Note: `USE_THIRD_PARTY_JSC=1` is required to use JavaScriptCore from this package until JavaScriptCore is removed from core react-native.
### Android
Add the following to your `android/gradle.properties`:
```properties
# Disable Hermes
hermesEnabled=false
# Enable third-party JSC
useThirdPartyJSC=true
```
## Usage
### iOS
Open AppDelegate.swift and overwrite `createJSRuntimeFactory` method:
```diff
import React
import React_RCTAppDelegate
import ReactAppDependencyProvider
import UIKit
+import ReactJSC
// AppDelegate code
class ReactNativeDelegate: RCTDefaultReactNativeFactoryDelegate {
override func sourceURL(for bridge: RCTBridge) -> URL? {
self.bundleURL()
}
override func bundleURL() -> URL? {
#if DEBUG
RCTBundleURLProvider.sharedSettings().jsBundleURL(forBundleRoot: "index")
#else
Bundle.main.url(forResource: "main", withExtension: "jsbundle")
#endif
}
+ override func createJSRuntimeFactory() -> JSRuntimeFactoryRef {
+ jsrt_create_jsc_factory() // Use JavaScriptCore runtime
+ }
}
```
### Android
Open `MainApplication.java` and overwrite `getJavaScriptExecutorFactory` method:
```diff
+import io.github.reactnativecommunity.javascriptcore.JSCExecutorFactory
+import io.github.reactnativecommunity.javascriptcore.JSCRuntimeFactory
+import com.facebook.react.bridge.JavaScriptExecutorFactory
+import com.facebook.react.modules.systeminfo.AndroidInfoHelpers
class MainApplication : Application(), ReactApplication {
override val reactNativeHost: ReactNativeHost =
object : DefaultReactNativeHost(this) {
override fun getPackages(): List =
PackageList(this).packages.apply {
// Packages that cannot be autolinked yet can be added manually here, for example:
// add(MyReactNativePackage())
}
override fun getJSMainModuleName(): String = "index"
override fun getUseDeveloperSupport(): Boolean = BuildConfig.DEBUG
override val isNewArchEnabled: Boolean = BuildConfig.IS_NEW_ARCHITECTURE_ENABLED
override val isHermesEnabled: Boolean = BuildConfig.IS_HERMES_ENABLED
+ override fun getJavaScriptExecutorFactory(): JavaScriptExecutorFactory =
+ JSCExecutorFactory(packageName, AndroidInfoHelpers.getFriendlyDeviceName())
}
+ override val reactHost: ReactHost
+ get() = getDefaultReactHost(applicationContext, reactNativeHost, JSCRuntimeFactory())
override fun onCreate() {
super.onCreate()
SoLoader.init(this, OpenSourceMergedSoMapping)
if (BuildConfig.IS_NEW_ARCHITECTURE_ENABLED) {
// If you opted-in for the New Architecture, we load the native entry point for this app.
load()
}
}
}
```
## Maintainers
- [Callstack](https://callstack.com/) – A Total Software Engineering Consultancy that transforms organizations and teams through transformative apps.
- [Expo](https://expo.dev/) - An open-source platform for making universal native apps for Android, iOS, and the web with JavaScript and React.
### Special Thanks
Special thanks to the team who worked on the initial extraction of JavaScriptCore from core react-native:
- [Riccardo Cipolleschi](https://github.com/cipolleschi)
- [Nicola Corti](https://github.com/cortinico)
- [Kudo Chien](https://github.com/Kudo)
- [Oskar Kwaśniewski](https://github.com/okwasniewski)
- [jsc-android](https://github.com/react-native-community/jsc-android-buildscripts) - This project uses **jsc-android** under the hood, which is supported by [Expo](https://expo.dev), [Software Mansion](https://swmansion.com/), and [Wix](https://www.wix.engineering/).
## License
Everything inside this repository is [MIT licensed](./LICENSE).