Give your simulator superpowers

RocketSim: An Essential Developer Tool
as recommended by Apple

Issue 346
Oct 20, 2026

This week's SwiftLee Weekly covers:

  • some View?
  • A Swift 6.4 change for package maintainers
  • A new CLI shipped in Xcode 27.2 beta

Enjoy this week's SwiftLee Weekly!

THIS WEEK'S BLOG POST

​SwiftUI Performance: Find Redraws in Xcode Instruments​

Agents write more and more of our code, including SwiftUI Views. What it doesn't do as well yet is ensuring great performance, preventing unnecessary redraws. Luckily, there's a way to do this!
​avanderlee.com​

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CURATED FROM THE COMMUNITY

​Swift 6.4 Support and the Move to Swift Build on the Swift Package Index Blog​

If you're a maintainer of open-sourced Swift packages, this is an important change to be aware of!
​swiftpackageindex.com​

​some View? without parentheses in Swift 6.4​

Apparently, you can now use some View? since Swift 6.4. Sarunw explains how it works.
​sarunw.com​

​Xcode Projects for the Command Line and Coding Agents​

The latest Xcode beta sneaked in a brand new CLI. Artem Novichkov explains what you can do with it and how it connects to the new project format.
​artemnovichkov.com​

​ArrangementView in SwiftUI: split and overlay layouts for iPhone Duo​

You should be getting closer to iPhone Duo ready, but if not yet, you'll enjoy this article by Natalia Panferova, full of supporting visuals.
​nilcoalescing.com​

​Why my Swift debouncer got 50× faster​

I love going deep on improvements, measuring percentage of change along the way. Though, I've not been going as far as Ivan Magda did for his Swift debouncer, ha!
​ivanmagda.dev​

SwiftLee WEEKLY GIVEAWAY

Do iOS Conference Ticket Winner

For the past 2 weeks, you've been able to join the Do iOS Conference ticket giveaway. I'm happy to announce Arjen Molhoek as the winner of this month's giveaway.

It's still not too late to buy yourself a ticket. Go to Do iOS, and see you in a few weeks?

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

What if you can't go to parties?

Not long ago, I got in touch with the organization behind De Special Social Club. They organize events for young adults with disabilities, to fight loneliness. They showed me this video (LinkedIn) of a party hosted in my neighbourhood, directly helping young adults who live around me.

I hosted parties before I started SwiftLee, so this really hit home. They need funding to keep organizing these parties regularly, so I decided to help.

Until Wednesday Oct 20th, 23:59 Amsterdam Time, I’m donating all my earnings from my apps to De Special Social Club. That’s what I receive from new purchases of RocketTrace, RocketSim, MCP Beast, and Video Compressor after Apple’s cut.

If you were already planning to try one of these, today is a good moment to do it! I’ll share the total in the next issue. Thanks in advance!

{% assign referral_count = subscriber.rh_totref | default: 0 | plus: 0 %}{% if subscriber.rh_reflink != blank %}UNTIL NEXT TIME

{% if referral_count >= 30 %}You’re one of SwiftLee Weekly’s top advocates

You’ve referred {{ referral_count }} developers and reached every current reward. Thank you for helping SwiftLee Weekly grow.

{% elsif referral_count >= 10 %}You’ve unlocked Swift Concurrency Course access

You’ve unlocked Swift Concurrency Course access as you’ve referred {{ referral_count }} developers.

{% assign referrals_needed = 30 | minus: referral_count %}Refer {{ referrals_needed }} more to unlock RocketSim Pro Lifetime.

{% elsif referral_count >= 3 %}You’ve reached your first referral reward

You’ve referred {{ referral_count }} developers. {% assign referrals_needed = 10 | minus: referral_count %}Refer {{ referrals_needed }} more to unlock Swift Concurrency Course access.

{% elsif referral_count == 2 %}One more referral unlocks your first reward

You’ve referred two developers. One more unlocks 50% off RocketSim Pro Yearly.

{% elsif referral_count == 1 %}You unlocked my 5 agent workflows

I’ve sent the reward to your inbox. You’re now two referrals away from 50% off RocketSim Pro Yearly.

{% else %}Refer one developer. Get my 5 agent workflows

Know a Swift or iOS developer who would enjoy SwiftLee Weekly? Refer one confirmed subscriber, and I’ll send you the five agent-powered workflows I use for marketing, App Store metadata, support, performance, and Xcode disk cleanup.

Your rewards continue from there: reach three referrals to unlock 50% off RocketSim Pro Yearly.{% endif %}

Your personal referral link

​{{subscriber.rh_reflink}}​

Share by email · WhatsApp · LinkedIn · X/Twitter · Bluesky​

{% if referral_count < 30 %}Rewards:

  • 3 referrals unlock 50% off RocketSim Pro Yearly
  • 10 unlock Swift Concurrency Course access
  • 30 unlock RocketSim Pro Lifetime.{% endif %}

​See your rewards and progress →​

{% endif %}Thank you so much for your support, and until next Tuesday,

Antoine

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