Give your simulator superpowers

RocketSim: An Essential Developer Tool
as recommended by Apple

Issue 284
Aug 12, 2025

This week's SwiftLee Weekly covers:

  • @isolated(any)
  • New Observations API
  • SwiftUI for macOS Tahoe

Enjoy this week's SwiftLee Weekly!

THIS WEEK'S BLOG POST

​Async await in Swift explained with code examples​

Everybody talks about Swift 6.2 and approachable concurrency, but what if you're still working with closure-based code? Migrating to async-await is your first step. Though, should you do that before or after migrating to Swift 6+?

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CURATED FROM THE COMMUNITY

​Streaming changes with Observations​

While this new API requires latest OS versions, I believe it’s going to have a big impact in how we write code. I’d even say, combined with Concurrency, it might allow us to move away from Combine completely. If you want to read more, here’s another article covering the topic.
​swiftwithmajid.com​

​@isolated(any)​

Swift Concurrency introduced a lot of isolated keywords and one of them is @isolated(any). You might have seen it, probably not (yet) used it. Mattt explains what it does.
​nshipster.com​

​Define the scroll edge effect style of a scroll view for Liquid Glass​

Different scroll edge effect styles impact the readability and experience of your iOS 26-supporting app. Learn how to pick the best one for your scroll views.
​createwithswift.com​

​SwiftUI for Mac 2025​

I’m building mostly for Mac these days, and loved this overview article of SwiftUI changes in macOS Tahoe.
​troz.net​

​Working with partially generated content in Xcode previews​

What if you want to show previews of in-progress changes for generated content? Artem Novichkov shares his solution.
​artemnovichkov.com​

NEW COURSE UPDATE

​Swift Concurrency Course Update​

My in-depth concurrency course got a large update and now offers a dedicated Core Data & Swift Concurrency module.

I've also added 10 new lessons, including:

  • Isolated conformance to protocols
  • Using isolated synchronous deinit
  • When to use discarding task groups

Altogether, the course now offers 65 lessons and 10 assessments and it's still available for a reduced launch offer price.

I offer students to share a testimonial after completion and one student wrote:

“For some reason, I always thought that a course had to be created by big companies to be good. I’m impressed by how valuable and accessible a course created by the community can be.”

WHAT I'M WORKING ON

Apple Workshops in Amsterdam

While I just arrived back from my 1-week holiday, I'm already deep into a busy work week. From Tuesday till Thursday, I'll be visiting Apple Workshops in Amsterdam to bring the new macOS Tahoe design to RocketSim.

Weeks like these require me to prioritize carefully. I only have today to prepare my weekly article, this newsletter, and handling all emails from the past week. This is also why I decided to update an older article instead of writing a complete new one to save myself time.

While I'm writing this from my Mac mini (self-hosted GitHub runner instance), I'm running the latest public beta update on a separate partition. The workshops require an up to date device so you can get started adopting new APIs right away.

So you might wonder: didn't you already adopt these new designs? You must have been excited right after WWDC!

Well, I was excited, but I decided to focus on Swift Concurrency first. RocketSim is now in a state where most of the code is migrated to strict concurrency, allowing me to switch focus completely to updating all UI elements. So yes, I was ánd I still am excited!

My goal is to adopt RocketSim's windows to macOS Tahoe first. This will especially be challenging for the Network Monitor, side window, and settings screen. Eventually, I'd love to integrate into Shortcuts and allow for more automations. Busy times ahead!

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Thank you so much for your support, and until next Tuesday,

Antoine

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