Setting up UniFFI for iOS, Simulators, and watchOS

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Mobile: A different way using Rust?

There are some great resources out there on UniFFI already such as this post, but it doesn’t cover watchOS, so let’s take a quick tour through what I’ve set up in the example repository https://github.com/Tehnix/template-mobile-wasm.

We’ve set up four crates:

• appy: Our Leptos App, Capacitor, and the XCode project
• capacitor-rs: Bridging code between the Capacitor JS library and our Rust code
• shared: Our shared code that we might use in appy, and also want to expose in Swift to use in our Widgets or watchOS App
• mobile: Where we will generate the Swift bindings from via UniFFI, reexporting everything from shared that’s made available to UniFFI via the macros

I won’t go over the details to get these to play nicely with Cargo and Workspaces, check out the repository for that. Let’s instead focus on a simplified version of what mobile does (the rest assumes you’re in the mobile/ directory).

💡 Looking for Android support? This is already added in the template repository above. Otherwise…