Give your simulator superpowers

RocketSim: An Essential Developer Tool
as recommended by Apple

Issue 287
Sep 02, 2025

This week's SwiftLee Weekly covers:

  • Dealing with Xcode migrations
  • Debugging Swift Concurrency
  • Controlling warnings in Swift Packages

Enjoy this week's SwiftLee Weekly!

THIS WEEK'S BLOG POST

​@ViewBuilder usage explained with code examples​

It's one of the most used result builders in SwiftUI: @ViewBuilder. Even if you're new to this attribute—you're already using it if you're writing SwiftUI code. Unde

SPONSORED

​Fastlane alternative - Codemagic CLI tools​

Are you tired of Ruby and Fastlane installation issues? There's got to be a better way! Discover Codemagic open source CLI tools. It is not a drop-in replacement for all of what Fastlane does (screenshots for example), but we use it at Codemagic to build and publish iOS and Android apps, also versioning and device provisioning. View on GitHub.

CURATED FROM THE COMMUNITY

​Building a design system at Genius Scan​

Design systems are incredibly powerful, yet there are few blogs that cover the topic. I was happy to see John Sundellshare his knowledge, as I know he has several years of experience on the subject.
​swiftbysundell.com​

​Creating amazing loading animations with SF Symbols.​

SF Symbols are more than static icons. If you get yourself familiar with animation options, you’ll be able to add much more joy to your apps!
​danielsaidi.com​

​Xcode Migrations: From Stone Age to AI Mastery​

As an indie developer, it’s easy to migrate to a new Xcode release. For larger teams, however, it can be quite the challenge. It took Qonto several weeks to apply the enhancements. P.S., they’ve also been using RocketSim for years to enhance their team’s productivity!
​medium.com​

​Debugging Swift Concurrency: "Am I on the Main Actor?" (Not the Main Thread)​

Thread.current and Thread.isMainThread don’t work with Swift Concurrency, so what do you do instead? This article explains.
​swiftyplace.com​

​Treating Warnings As Errors In Swift Packages​

Swift 6.2 allows you to control warnings in Swift Packages, which can be useful to enable features like treating warnings as errors. Keith Harrison explains how it works.
​useyourloaf.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.

There has been no change in the past 7 days.

WHAT I'M WORKING ON

Concurrency Videos and Pragma Conference

Conference season is around the corner and allows you to visit great talks around the world. Unlike other years, I'm taking it easy this year. I'm so far only scheduled for Pragma Conference where I'll give a talk on Swift Concurrency.

I love win-wins, so while preparing the talk, I'll also record new videos for my concurrency course. To make it a win-win-win, I'll also use the materials to produce some key concept videos for YouTube. Time spent well!

If you're working on side projects while having a full time job, you'll love the win-wins. They've been crucial in my growth while I was working at WeTransfer back in the days. It's also why all my products (blog, newsletter, courses, RocketSim) target the same audience: developers. I only have to build an audience once and I can benefit from growth for all products.

This insight could open your eyes and if it does, I'm sure you'll enjoy more of my tips at going-indie.com.

Meanwhile, we're getting closer to the final release of macOS Tahoe, iOS, iPadOS, etc. Apple announced a special event for the 9th of September which will likely announce the final release dates, too. Make sure to finish your redesign and new API adoptions!

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

Antoine

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