Matt Massicotte iOS Articles & Videos

There was a great Swift Group Lab session recently. And this follows a similar concurrency-specific session which was also wonderful. I think the format is a little challenging for the panelists, but they manage to do a great job regardless. It's so valuable to have real questions answered by the people that built the stuff. And I happen to really enjoy the live, unscripted discussion.

Recently, I was asked an interesting question. If the purpose of an actor is to protect mutable state, is a stateless actor pointless?

At first, I thought it was an easy answer. Actors exist to define a little, protective bubble around state. They "isolate" data away from any unsafe accesses. An actor that has nothing to isolate seems like a strange thing.

Can such an arrangement serve a purpose?

I have never published a WWDC wishlist, or ever even really thought much about one before. But, there are some areas that I'm definitely interested in, so I thought it would be fun to share.

Here's my "watchlist" of things I'll be paying special attention to.

The article shows how Swift 6 concurrency features (default MainActor, isolated conformances, Sendable) affect protocol design. Using a simple DatabaseModel protocol, it explains why a conformance can fail due to isolation mismatch with Identifiable. It walks through solutions like changing default isolation, using nonisolated, requiring Sendable, or switching to async protocol requirements.