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SwiftLee Weekly by Antoine van der Lee

SwiftLee Weekly - Issue 336

Published about 2 months ago • 5 min read

This week's SwiftLee Weekly covers:

  • Xcode 27’s new MCP server experience
  • Sendable and @Sendable closures explained
  • Adaptive toolbars and concentric buttons in SwiftUI

Before we dive in: this weekend I revealed my next app. RocketTrace turns intimidating Instruments traces into a ranked list of performance findings, so you know what to fix instead of where to look. Early beta signups are open, and I'm inviting testers in small waves: join the waitlist here.

Enjoy this week's SwiftLee Weekly!

THIS WEEK'S BLOG POST

​Sendable and @Sendable closures explained with code examples​

Sendable, unchecked sendable, @Sendable in closures: its helpful for thread-safety at compile time, but it's still a topic or technique that's hard to fully understand. This week's updated article takes you through all the details.
​avanderlee.com​

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CURATED FROM THE COMMUNITY

​Xcode 27 Beta 5 Release Notes​

As iOS developers, I recommend always checking the release notes of Xcode. This week's new beta introduces a preview of a new MCP server experience which proves Apple isn't only focusing on their own IDE support.
​developer.apple.com​

​Using AI while exercising your critical thinking​

Trusting AI for development fully might lead to false assumptions: what if you believe something that's wrong? That's why I always review through PRs and train my agents through compounding AGENTS.md updates.
​swiftrocks.com​

​Concentric Buttons with OS 27's SwiftUI APIs​

Concentric corners resulted in several new SwiftUI APIs, like this one for buttons and GeometryProxy as explained by Alexander Weiss.
​alexanderweiss.dev​

​Adaptive SwiftUI toolbars in iOS 27​

Have you already explored the new SwiftUI toolbar APIs in iOS 27? If not, this article by Natalia Panferova will help you out!
​nilcoalescing.com​

​Controlling Orphans in SwiftUI Text using an undocumented method​

Text handling is always challenging, so it surprises me that this undocumented SwiftUI method didn't make it into the standard library yet! Fatbobman shares how it works and what the risks are.
​fatbobman.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

An Open Standard for Agent Plugins

In case you missed it, there's now a new open standard for Agent Plugins.

I like to stay on top of things, so I've been working hard on updating my Agent Skills towards this new standard. The goal is to give you access to all my skills through this open format by the end of this week.

​My Swift Concurrency Agent Skill should already work, so feel free to give it a try if you will. I'll focus on my SwiftUI one next, and all others right after.

Agent Plugins make distribution of Agent Skills simpler. Clients supporting the format can discover and load the skills consistently, so I'm sure this will bring my agent skills to a higher level.

UNTIL NEXT TIME

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Rewards: 3 referrals unlock 50% off RocketSim Pro Yearly, 10 unlock Swift Concurrency Course access, and 30 unlock RocketSim Pro Lifetime.

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

Antoine

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SwiftLee Weekly by Antoine van der Lee

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

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