--- title: Creating browser extensions in Xcode framework: browserenginekit role: article role_heading: Article path: browserenginekit/creating-browser-extensions-in-xcode --- # Creating browser extensions in Xcode Configure your Xcode project to support your alternative browser engine. ## Overview Overview Deliver your web browser as a browser app and a collection of extensions, described in Designing your browser architecture. Create a separate target in your Xcode project for each of the three kinds of extension: web content extension, rendering extension, and networking extension. Create your Xcode project Create a new Xcode project for your browser app and extensions: In Xcode, choose File > New Project. Select the iOS App template, and click Next. Give your project a name, and click Next. Choose a location to save your project, and click Create. Create extension targets in Xcode Open your Xcode project, and follow these steps for each of the three extension types: Select your Xcode project in the Project Navigator. Click the Add (+) button at the bottom of the targets list. Select the iOS Generic Extension template, and click Next. Give the extension a name, and ensure your browser app is chosen for the Embed in Application setting. Click Finish, then cancel the request to activate the extension target’s scheme. Select the new target in the Project Editor. Switch to the Info tab. Expand the disclosure triangle next to EXAppExtensionAttributes. Edit the value for EXExtensionPointIdentifier, and enter the appropriate value from the list based on the extension type: Build for pointer authentication Browser apps that include alternative browser engines must use the arm64e instruction set for all executables, including the extensions, in order to use the system’s pointer-authentication protection on devices that support it. Build your browser app as a universal binary that also supports the arm64 instruction set to target iPad models that support alternative browser engines and don’t support arm64e instructions. important: You can develop and test your alternative browser engine using the arm64 instruction set. To distribute your browser that includes an alternative browser engine, you need to support the arm64e instruction set. To configure your Xcode targets to use the arm64e instruction set: Select the Xcode project in the Project Navigator. Select your target. Open the Build Settings Tab. Click the disclosure button to the left of the Architectures build setting. Click the Add (+) button that appears when you move the mouse pointer over the Debug build configuration. Change the SDK in the new row from “Any SDK” to “iOS”. Enter the value arm64e for the build setting for the iOS SDK. Repeat steps 5-7 for the Release build configuration. Repeat steps 2-8 for each target in your browser app project. Alternatively, if you use Xcode configuration files to manage build settings for your targets, add this line to your configuration file: ARCHS[sdk=iphoneos*]=arm64e important: Don’t build your target with the arm64e instruction set for Simulator destinations. Simulator for iPhone doesn’t support arm64e instructions. If your Xcode workspace includes Swift Packages as dependencies for your targets, use workspace settings to build the packages using the arm64e instruction set. In Terminal, run these commands: % plutil -create xml1 MyWorkspace.xcworkspace/xcshareddata/WorkspaceSettings.xcsettings % plutil -insert iOSPackagesShouldBuildARM64e -bool YES MyWorkspace.xcworkspace/xcshareddata/WorkspaceSettings.xcsettings Adopt the correct entitlements To act as a person’s web browser, your app requires the default-browser entitlement (see Preparing your app to be the default web browser), and the Web Browser Engine Entitlement that enables your app to separate core tasks of an alternative browser engine into dedicated extensions. note: Apps that aren’t browsers that use an alternative browser engine for in-app browsing need to add the Embedded Browser Engine Entitlement and Embedded Browser Engine Association Entitlement rather than the default-browser entitlement and Web Browser Engine Entitlement. In addition, an app that isn’t a browser needs to include: The alternative browser engine in its own executable or as a dynamic library The BEEmbeddedWebBrowserEngine and BEEmbeddedWebBrowserEngineVersion keys in its target properties embedded-web-browser-engine in its UIRequiredDeviceCapabilities target property The embedded alternative browser only needs to use the arm64 instruction set (not arm64e). It can’t include any web browser extensions or use just-in-time (JIT) compilation. Each of your browser app’s extensions need to add the the following entitlements with a value of true: To use the extension entitlements, compile your host app and extensions with the arm64e instruction set. In Japan, browser apps are required to enable hardware memory tagging (see com.apple.security.hardened-process.checked-allocations). To protect your users, Apple also strongly recommends that browser apps enable memory tagging in the European Union. In addition, you can optionally add the following entitlements: To allow JIT compilation of website scripts, your content extension uses the Allow execution of JIT-compiled code entitlement entitlement with a value of true, and Extended Virtual Addressing Entitlement with a value of true. For more information, see Protecting code compiled just in time. You can’t give this entitlement to your browser app, rendering extension, or networking extension. To transfer memory attribution between extensions, your content extension uses the com.apple.developer.memory.transfer_accept entitlement, and your rendering extension uses the com.apple.developer.memory.transfer_send entitlement, both with the browser apps’ bundle identifier as the value. For more information, see Attributing memory to a content extension. To restrict access to the system notification service in your web content extension, add the com.apple.developer.web-browser-engine.restrict.notifyd entitlement with the value true. For more information, see Limiting resource access in web content extensions. For more information on adding entitlements to targets in Xcode, see Entitlements. important: App Store Connect won’t accept your app if your non-browser app includes any of the entitlements for web browsers and their extensions described in this section, or you use the entitlements on other web browser components or with different values than those listed here. You must use all of the entitlements listed here only for the purposes described, for the relevant components of your browser app. Target devices with required capabilities Add the string web-browser-engine to the UIRequiredDeviceCapabilities array in your target’s properties, to ensure that people can only download your app on devices that support browser apps with alternative browser engines. If your browser app only supports the arm64e instruction set, also add arm64e to UIRequiredDeviceCapabilities. For more information, see Required Device Capabilities. Test your web browser Development of a web browser that uses an alternative browser engine can occur anywhere in the world. Xcode allows running development or Ad-Hoc signed builds of the app on Simulator but device support varies by region: ## See Also ### Browser extensions - [Extension life cycle](browserenginekit/extension-lifecycle.md) - [Extension resources](browserenginekit/extension-resources.md)