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Give your simulator superpowers

RocketSim: An Essential Developer Tool
as recommended by Apple

Issue 291
Sep 30, 2025

This week's SwiftLee Weekly covers:

  • Next-level Xcode Simulator recordings
  • Additional iOS 26 documentation for Agents.md
  • Swift Package Manager traits

Enjoy this week's SwiftLee Weekly!

THIS WEEK'S BLOG POST

​Derived Data: 5 Things iOS Developers Do Wrong​

It's one of the most important directories when it comes down to development with Xcode: The Derived Data folder. Some of you might know all about it, some will hear about it for the first time in this newsletter. I've explored it quite a bit during my career and while developing RocketSim, so it's time to prevent you from the most common mistakes.

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CURATED FROM THE COMMUNITY

​Xcode 26’s Additional Documentation for Agents​

Add this directory to your Agents.md to enrich e.g. Cursor or Codex with iOS 26 specific features.
​x.com​

​Structuring universal links in iOS​

I always find it an interesting challenge to parse and handle deeplinks/universal links well. In this article, Natascha Fadeeva shares her way of managing these. Make sure to use this tool to test them!
​tanaschita.com​

​Accessing Swift Package Manager dependency versions at runtime​

What if you want to show the exact version of a 3rd party dependency you’re using? The technique described in this article can help.
​annema.me​

​All about Swift Package Manager Traits​

Swift Package Manager traits are new since Swift 6.1 and allow you to turn package features on and off. This can be useful to conditionally enable features, something I’ve at least been looking for in the past!
​theswiftdev.com​

​How to hide a view in a screenshot​

What if someone creates a screenshot while your app is active, showing sensitive data? Vincent Pradeilles shares an API that allows you to hide views on screenshots.
​swiftwithvincent.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

Next-level Xcode Simulator Recordings

Xcode's Simulator allows you to create recordings, but it still lacks quite a few features that you would expect:

  • No way to add device bezels
  • Audio is not recorded
  • It's always a squared output, without a beautiful background
  • Touches are never displayed on recordings
  • The output resolution does not look great on socials

For years, RocketSim improved this experience. Yet, this week, I'm pushing the boundaries to another level.

​Check the demo video on LinkedIn → (You'll love Touch Attention Mode)

Oh, and while you're there, make sure to give my LinkedIn profile a follow: linkedin.com/in/ajvanderlee/​

I'm ramping up the content that I share on LinkedIn, including rich content like this.

Either way, RocketSim's next release is being reviewed, so make sure to download it from the App Store so you'll get these advanced recording capabilities later this week!

​

{% if subscriber.rh_reflink != blank %}EARN ROCKETSIM LIFETIME

Share and Earn RocketSim Lifetime & free Swift Concurrency Course access

Apple has recognized RocketSim as an Essential Developer Tool in the Mac App Store, and now you can get lifetime Pro access by sharing your unique referral link!
​​
How to get started:

​{{subscriber.rh_reflink}}
​​
Rewards:

Several subscribers have already helped me reach more developers and gained free access to RocketSim Pro and my Swift Concurrency Course — will you be next?{% endif %}

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

Antoine

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