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SwiftLee Weekly by Antoine van der Lee

SwiftLee Weekly - Issue 340

Published about 2 months ago • 5 min read

This week's SwiftLee Weekly covers:

  • iOS Simulator inside Claude Code, Cursor, or Codex
  • Reducing memory usage caused by Xcode Simulators
  • Foundation Models and images

Enjoy this week's SwiftLee Weekly!

THIS WEEK'S BLOG POST

​The iOS Simulator Inside Cursor, Claude Code, and Codex​

The way we develop apps changes, has changed, and will continue to change. In this week's article, I'm shining a light on my perspectives for today and for the future of agentic app development.
​avanderlee.com​

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CURATED FROM THE COMMUNITY

​MobAI-App/simslim: Run more iOS simulators on one Mac by disabling background daemons​

Disabling background daemons a simulator doesn't need is a smart trick to reduce memory pressure. Some devs consider this useful for regular development instead of only CI, but watch out: unexpected behavior could be caused by this (so I'm not yet doing this!)
​github.com​

​Building a sunburst diagram in Swift Charts​

Swift Charts are powerful and you might not always realize how much you can do with this. How about a sunburst diagram, as Natalia Panferova explains?
​nilcoalescing.com​

​Working With Images Using Foundation Models​

The Foundation Models improvements we got this year open up doors for many new app ideas. Working with images is another angle that could spark your next app idea, explained by Mohammad Azam.
​azamsharp.com​

​Codable errors are finally readable in Swift 6.3​

Codable errors in Swift, printed in your console, hard to read. It's no longer the case, as Sarunw explains!
​sarunw.com​

​Teaching Siri to talk about your favorite walks in Walk Mate​

Siri on iOS 27 should be able to talk about your app's data. Emre Degirmenci explains how it works.
​emredegirmenci.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

Finding new ways to integrate RocketSim into AI

This week's article shines a light on this more, but I want to share a bit more insight into the journey towards the first preview of RocketSim 17.

I’ve been exploring integration with Claude Code, Cursor, and Codex for a while. There are options to do it natively, but none of them were built once, run everywhere. Adding another release pipeline is far from ideal, and I already have the CLI and Agent Skill.

As I’m sure many of you do, I often build web pages using AI. What’s great about it is that I can run and validate the website directly inside the browser in Cursor. It made me wonder: why can’t we do the same for app development?

I started streaming the Simulator, which I had implemented fairly quickly: RocketSim’s CLI allows agents to stream and create screenshots or videos.

At first, I figured I’d rebuild RocketSim entirely, so I started creating the side window in the browser. Quickly, though, I realized I was optimizing for a completely different flow: agentic development. You’re not looking for the same tools, because you could do that using RocketSim natively. Instead, it should be a way to follow along with what the agent is doing and to provide the agent with feedback to continue its journey.

That’s how I started to evolve into a Simulator stream, combining worktree and branch information with accessibility tree insights and design feedback. Agents will write the code; you will provide feedback on the app’s behavior.

It’s still early days, and I’m actively using this version myself, but I’m keen to see where this goes. I’d love to get your ideas on the future of app development, so don’t hesitate to hit reply and share your dreams with me.

UNTIL NEXT TIME

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

Antoine

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