This week's SwiftLee Weekly covers:

• Apple Developer meetup during WWDC
• Draggable bottom sheet in SwiftUI
• Xcode Instruments x AI Agents

Enjoy this week's SwiftLee Weekly!

THIS WEEK'S BLOG POST

​Xcode Instruments Time Profiler: Improve performance with AI​

I'm a big fan of Xcode Instruments, but lately even more now that I found a good way to work with it using AI agents. In this week's article, I'll share you how I used it this week to gain 25x better performance for RocketSim's CLI.

SPONSORED

​Lessons Learned from Security Incidents in Mobile Apps​

Join Security Researcher and Pentester, Jan Seredynski, on May 12 as he dissects real-world security incidents in banking, food delivery, and e-commerce. From face verification bypass to location spoofing, he'll break down the anatomy of a breach and what teams can do differently to address them. Learn more​

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

CLI to control Xcode's Simulator

Controlling the Simulator using a CLI or via agents is not new. However, the solutions out there are not as optimized as I wish. I truly believe in an optimized workflow where less tokens are spent, and navigation performs faster.

​RocketSim's CLI is already live, but it's very much a first version. This week I'm working together with several teams that use RocketSim to optimize it to their needs. The elements and interact commands will be optimized for failure prevention. That means some CLI outputs might be a little more detailed, but they'll prevent agents from guessing or making mistakes. The outcome will be faster iterations and fewer tokens used.

Another benefit I truly believe in: RocketSim runs as a Mac app, allowing for caching and stateful responses. You'll be able to store pre-defined flows for your app or combine manual interaction with agentic involvement.

With the latter I mostly mean this scenario:

• Run rocketsim start_performance_trace from the terminal or via an agent
• Perform specific steps in your app, like starting an animation or refreshing a page
• Run rocketsim stop_performance_trace and let the agent analyze the results

RocketSim will share only what's needed:

• Network requests from the session
• Time Profiler output for that specific period
• Or any other data based on input flags

And all with token consumption in mind. Some of these features I've already got working and together with those teams, I'll make sure you'll get the best possible agentic workflow for iOS development.