Reader

In order to build reader you need the appropriate targets added to your Rust toolchain.

$ rustup target add aarch64-apple-ios aarch64-apple-ios-sim x86_64-apple-ios

x86_64-apple-ios is only necessary if you're on an Intel Mac, and aarch-64-apple-ios-sim if you're on Apple Silicon.

The Xcode build script will take care of actually building the Rust code.