I have an iOS SwiftUI app which uses some extensions like NotificationServiceExtension, NotificationContentExtension, WidgetExtension etc. I noticed that each extension uses its own process and has its own bundle with the .appex extension… and is packaged within the app bundle, with .app extension.

In my case, most of my logic is in C++ and when the app starts up, it needs to ‘startup’ the C++ layer. Now, in WidgetExtension, if it’s going to read data from disk and update its interface, I need to initialise my C++ layer first. The same can be said for NotificationServiceExtension. This is leading me to include all my C++ artefacts into the extension target as well.

Here’s my problem: If the size of my app (containing all my C++ artefacts) is 10MB and I’m using 20 extensions (say), the final size of the shipped app bundle is 10MB + (20 * 10MB) = 210MB, since extension bundle (.appex) is packaged within the app bundle (.app).

Since the app and the extensions are using the same C++ artefacts, I was hoping to have one binary in the bundle. The app and its extensions will point to this binary. When the app is launched, the app entry point (struct conforming to App protocol) is invoked, in case of widget, the widget entry point (WidgetBundle) is invoked and so on for each extension. This will reduce the final size of the app bundle. Is it possible to have one binary and the app target, all extension targets would use this binary for there functioning?