Snapp Technology
Hi folks,
Swift is in a strange, high-gear phase right now. Between the deep-dive into actor internals and the humbling realization that SwiftUI performance is mostly just a game of ‘spot the difference’ for the compiler, it feels like we’re finally peeling back the curtain on the machinery. And seeing millions of lines of Swift actually humming along in a browser via Wasm? That’s the kind of ‘future is now’ win that makes the struggle with ghosty animation bugs worth it. From Swift 6.4’s quality-of-life wins to Apple swallowing our favorite prototyping tools, this week is all about power gains and the growing pains that come with them.
Enjoy the mix!
Articles
News
Apple Acquires Award-Winning App ‘Play’
Apple officially announced their acquisition of Play, that clever SwiftUI prototyping tool. It’s off the App Store now, so we can only hope its best bits end up in Xcode soon. Who doesn’t want a more fluid way to iterate on our apps?
Swift
Bringing Goodnotes to the web with Swift and WebAssembly
Goodnotes just proved that we can actually run millions of lines of Swift in a browser using Wasm without sacrificing that 60 FPS ink feel. They shared a ton about using WASI threads and custom actor executors to keep things snappy. It’s a massive win for those of us wanting a truly shared codebase across iOS and the web.
Swift 6.4: What’s New in Concurrency
Swift 6.4 is sneaking in some really practical quality-of-life bits. Async defer is a godsend for cleanup, and cancellation shields finally let us finish critical work without being cut off. Also, those new warnings for ignored throwing tasks will save us from a lot of “why did this fail silently” debugging sessions.
Swift 6.4 Brings New Language Features and Swift Testing/XCTest Interop
Beyond concurrency, Swift 6.4 is cleaning up the edges with weak let and ~Sendable for when we need to be explicit about thread-safety. The interoperability between Swift Testing and XCTest is the real headline here, making the migration path a lot less painful. Plus, anyAppleOS is a nice touch to stop the boilerplate from piling up in our availability checks.
Actors in Swift: The Problem They Solve and How it Works
A deep dive into the “aha” moment of actor isolation. It cuts through the mystery of why we use them and warns us about the reentrancy trap—where the world changes under our feet during an await. If you’ve ever wondered why your actor state felt unstable, this is the read you need.
UI/UX
Debugging Notes on Two SwiftUI Animation Bugs
A raw look at chasing those ghosty SwiftUI animation bugs that only show up on specific iOS versions. One’s a lesson in why implicit animations are safer than withAnimation for complex trees, and the other is a weird case where if/else beats a ternary for identity reasons. It’s a reminder that sometimes a bit of “comment-it-out” intuition is all we’ve got.
SwiftUI Performance Is Not About Views. It Is About Diffing
Performance in SwiftUI isn’t about the number of views—it’s about whether the framework can actually tell what changed. The real culprits are usually non-diffable closures and lazy computed properties masquerading as views. The fix is to be explicit with Equatable and create real diffing boundaries by extracting actual view structs.
Tools
ATProtoKit
A solid Swift library for anyone looking to build on Bluesky or the AT Protocol. It wraps the complex xrpc and api logic into something that feels native to our language. It’s still unstable, but it’s the quickest way to get a bot or a client running without fighting the protocol from scratch.