Give your simulator superpowers

RocketSim: An Essential Developer Tool
as recommended by Apple

Issue 338
Aug 25, 2026

This week's SwiftLee Weekly covers:

  • Dynamic Profiles in Apple Foundation Models
  • StateReporter & MetricKit in iOS 27
  • What's new in Swift 6.4

Enjoy this week's SwiftLee Weekly!

THIS WEEK'S BLOG POST

@StateObject vs. @ObservedObject: The differences explained

The Observable framework makes these obsolete, but many projects still have old code using these property wrappers. Knowing their differences is important and also teaches you more on how SwiftUI works.
avanderlee.com

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CURATED FROM THE COMMUNITY

Apple Foundation Models: Hybrid AI with Dynamic Profiles

Apple's Dynamic Profiles help you switch between on-device and cloude-hosted models. The perfect balance and ideal if you're building for Apple's platforms. Peter Friese explains how it works.
peterfriese.dev

withContinuousObservation in Swift

The Observation framework remains one I want to explore further, even more so after reading about this new API in Artem Mirzabekian's article.
livsycode.com

Detecting (Evil) Dylibs

Not many know: I graduated on hacking iOS 4. Finding articles like this one by Patrick Wardle always spark my interest, and it's also highly valuable for those apps that require enhanced security.
objective-see.org

Building adaptive SwiftUI layouts with containerRelativeFrame()

Shoutout to Natalia Panferova for continously delivering high quality articles with supporting visuals. This one is a great way to better understand the containerRelativeFrame() API in SwiftUI.
nilcoalescing.com

iOS 27: StateReporter

The MetricKit framework is undervalued: it truly helped us a lot back in my days at WeTransfer. Anton Gubarenkoexplains a new framework that makes MetricKit reports even more valuable.
antongubarenko.substack.com

SWIFT EVOLUTION

An overview of last week's Swift Proposal state changes. Check them out when they're in review, as it's your opportunity to influence the direction of Swift's future.

WHAT I'M WORKING ON

A new home for this newsletter

As you're receiving this newsletter in your inbox, you're likely not reading it from the browser. However, there’s still value in serving each issue through the web. It allows you to go back in time and find valuable articles, but all issues together are also a goldmine of valuable content.

Each week, I curate the 5 articles I find the most valuable. There are weeks when I evaluate 30 new articles written that week. The result is a database of ‘best in class’ articles, and I felt I should surface them more. You can now find the most popular blogs from SwiftLee Weekly's curation and consider following them directly.

The changes in the Swift Evolution Proposals are also worth following along. In addition to receiving weekly updates in this newsletter, you can now browse proposal states directly. Or, if you want a more focused overview, you can navigate to pages like What’s new in Swift 6.4 and find an overview of related proposals.

I’ve spent the past few weeks slowly building this website in the background, based on my already-written newsletter. I truly hope this is a great addition to those exploring Swift in more depth, and I’d love to hear your feedback!

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