SwiftLee Weekly - Issue 323


This week's SwiftLee Weekly covers:

  • App copywriting & Agents
  • SwiftData's new HistoryObserver
  • Timezone testing without physically traveling

Enjoy this week's SwiftLee Weekly!

THIS WEEK'S BLOG POST

​How to Test iOS Apps in Different Time Zones on a Physical iPhone​

WWDC introduced a few changes that were quite hidden, but I’m happy to surface them today. RocketSim now allows you to simulate locations on a physical device and iOS will take it seriously: expect focus mode changes, driving mode enabled, and timezone switches.
​avanderlee.com​

SPONSORED

​Share your AI agent’s work with your team​

Your agent generates a report, dashboard, or prototype as HTML or Markdown. display.dev turns it into a secure URL your team can open with their existing work login, comment on inline, and send back to any agent through MCP. Works with Cursor, Codex, Claude Code, and more. No viewer accounts, no seat management, no vendor lock-in. Learn more.

CURATED FROM THE COMMUNITY

​Building adaptive non-modal panels in SwiftUI​

What if SwiftUI’s sheet API is not sufficient enough? You’ll built your own custom solution, but with system-like APIs. Matthaus Woolard shares the details.
​nilcoalescing.com​

​Copywriting with Agents and…Apple Designers?​

Agents can write code, but they can also help you write better copy. Jordan Morgan explains the impact it had on his app.
​swiftjectivec.com​

​Geometry, compositing and drawing groups in SwiftUI​

SwiftUI modifiers aren’t always easy to distinguish, like geometry vs. compositing vs. drawing group. Do you know the differences? Natalia Panferova will help you out!
​nilcoalescing.com​

​Syncing SwiftData With A Custom Backend Using HistoryObserver​

WWDC introduced SwiftData improvements, and Mohammad Azam takes you through the new HistoryObserver.
​azamsharp.com​

​Revisiting the JET iOS Modular Architecture in 2026​

What if you designed a code architecture back in 2019, when CocoaPods wasn’t yet deprecated, and monorepos were still debatable? Alberto De Bortoli revisits his old article with their new vision.
​albertodebortoli.com​

WHAT I'M WORKING ON

Agentic coding fundamentals for developers

It's been a while since I updated you on my new course built around Agentic Coding fundamentals. The main reason was busy times with RocketSim, WWDC, conferences, but also, I'm still learning so much.

Yet I did keep track of all my learning. I've created a diary of my own progress, which I can now use to write the course modules. Altogether, I've finished a few of the modules already.

Unlike with my concurrency course, I'm now going to only release the course when it's completely finished. Probably still in phases, so the first to join the waitlist will get the quickest access.

You might think “aren’t courses dead?” or “How will you keep the course up to date, AI is moving so fast?” and you’ll be partly right. However, I believe we lack fundamental education on how agentic coding works in general, for which this course is the answer.

It’s purposely written without focusing on a single IDE or tool. Whether you use Cursor, Claude, or Codex: the fundamentals behind it are similar. What are models? How do tokens work? What is a good prompt? From simple to advanced questions, but also the creativity of how you can use these tools to the fullest.

Stay tuned, and don’t forget to join the waitlist.

UNTIL NEXT TIME

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

Antoine

SwiftLee Weekly by Antoine van der Lee

Swift Evolution updates, 5 top community articles covering Swift development topics.

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