Many Alpha plugins use Objective-C Runtime features underneath. Swift classes exposed to Objective-C will work, but some features might not be available, such as Heap inspection. As long as Swift's Introspection is limited, this will not change. Alpha will still support Swift applications as much as it is possible with Objective-C.

Alpha is meant to be used as a development and debugging tool. Some plugins of Alpha may use private API's to collect information. There are no private warning API's triggered to support TestFlight builds and it is possible to exclude those plugins. In either case, Alpha should not be included in Production App Store builds, due to security reasons.