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SwiftLee Weekly by Antoine van der Lee

SwiftLee Weekly - Issue 317

Published 3 months ago • 5 min read

This week's SwiftLee Weekly covers:

  • 6 new Agent Skills for Xcode
  • WWDC 2026 Pins
  • Swift 6.3 and Xcode 26.4 must-knowns

Enjoy this week's SwiftLee Weekly!

THIS WEEK'S BLOG POST

​Xcode Build Optimization using 6 Agent Skills​

Not one, but six new Agent Skills! Early adopters improved Xcode build times by 78%. I've been working on this for the past weeks and optimized it with the help of many community contributors (thank you all!!). Now it's time to let you benefit and optimize your Xcode build performance.

Besides these new Agent skills, I also offer skills for Swift Concurrency, SwiftUI, Swift Testing, and more. You can install all my Agent Skills here.

SPONSORED

​Stop waiting. Start shipping.​

Shared runners, queued jobs, throttled Xcode builds — CI shouldn’t slow you down. Flow Swiss gives you dedicated Apple Silicon machines, yours alone. No noisy neighbors, no limits — just raw Mac mini and Mac Studio performance in the cloud, ready in seconds. New Xcode dropped? You’re ready day one. Learn more.

CURATED FROM THE COMMUNITY

​WWDC 2026 Pins – Because We All Collect Them Anyway​

Let’s be honest: half of WWDC is code, and the other half is pins. To celebrate Apple’s 50th anniversary and Dubdubs, Clément Sauvage created a limited-edition enamel pins collection for developers who’ve been there and Apple enthusiasts. The project quickly reached 100% funding, proving that we really like pins. I’ve already ordered mine, and they’re still available (for now).
​kickstarter.com​

​88: SwiftLee – Antoine van der Lee​

Launched by Charlie Chapman is one of my favorite podcasts and this time I’ve been invited! I couldn’t be more excited, especially as I got to share a lot of background stories I didn’t share before.
​launchedfm.com​

​Swift 6.3 Released​

The next Swift release is here and introduces features like weak let, package & build improvements, and 7 Swift Testing improvements.
​swift.org​

​Package Traits in Xcode​

Xcode 26.4 is now generally available, introducing Agentic Coding support to you all. But it contains more! Package traits, something Matt got excited about.
​massicotte.org​

​Xcode 26.4 Simulator Paste Is Broken: Here’s the Workaround​

Before you start debugging endlessly: paste is broken in the Xcode 26.4 Simulator. You can use Junda’s workaround or use the “Copy to Simulator” button in RocketSim.
​samwize.com​

WHAT I'M WORKING ON

Hello, Shanghai!

I'm writing this newsletter from the Airport in Shanghai. I just finished my trip to Let's Vision conference and had an amazing experience. The conference is so well organized and it was amazing to meet the community all the way here.

At the same time, I realized more than ever how important it is to localize our apps. China is quite different compared to the Netherlands with apps like Alipay and WeChat, but also: their language is quite different from English.

Obviously, it's also the other way around. English characters are not easy to understand for Chinese people, and this is not an exception to China alone. I've started working on a translated version for RocketSim right away as I honestly assumed that developers using Xcode would understand English either way.

This is really just a quick prototype, but it allowed me to test it out at the conference and validate the concept. It proved another benefit of traveling around: meeting your end-users.

Altogether, I've had a fantastic experience. I can't wait to go back home to my wife and kids (a crying 4-year old over FaceTime telling he misses you doesn't help), but I'll bring back a bag of inspiration and energy to build the next phase of RocketSim.

UNTIL NEXT TIME

Continue your Swift development journey

I hope you've enjoyed this week's content. You don't have to wait till next Tuesday for more insights, I share every day on these channels:

Or earn lifetime access to RocketSim & my Swift Concurrency Course by becoming an affiliate of my newsletter.

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

Antoine

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