Antoine van der Lee — iOS developer, tech lead, and creator of SwiftLee, helping developers grow their Swift skills, build successful side projects, and advance their careers through in-depth tutorials, podcasts, and mentorship.
29 articles from this blog
Swift Testing is the modern framework for writing tests in Swift, built around expressive macros like @Test, #expect, and #require. It’s the successor
Learn how Sendable and @Sendable closures work in Swift concurrency, with code examples ensuring data-race safety.
Learn how to use @MainActor in Swift to ensure main thread execution with code examples, including Swift 6.2 changes.
Learn how to free up Xcode disk space using an AI agent with an open-source cleanup skill.
Learn how to test iOS apps in different time zones on a physical iPhone using RocketSim and Xcode 27.
Introduces Diagnostics, an open-source library that generates detailed HTML reports to help developers debug app issues faster using AI agents.
Learn how to use the Swift defer keyword with code examples, including async cleanup in Swift 6.4.
Explains Swift's memberwise initializer for structs with code examples, including default values and Swift 6.4 improvements.
Overview of new concurrency features in Swift 6.4, including async defer statements and other improvements from Swift Evolution proposals.
Analyzes SwiftUI best practices from Apple's Xcode 27 Agent Skill, covering view structure, data flow, performance, and more.
Guide to exporting and using Xcode 27's official Agent Skills in third-party IDEs like Claude, Codex, and Cursor.
A developer shares predictions and wishes for WWDC 2026, focusing on AI-driven development, Xcode improvements, and iOS tooling.
Guide on using Xcode Instruments to optimize Swift Concurrency code, covering templates, instruments, and performance analysis.
Learn how to record physical iPhone app preview videos with device bezels using RocketSim for App Store marketing.
Optimizing AI agents for Xcode Simulator automation using RocketSim CLI, reducing tokens and improving speed.
Explores unexpected suspension points in Swift Concurrency that can impact app performance, with a focus on main-thread usage.
Explains Swift Concurrency's immediate tasks (Task.immediate) for performance-sensitive code, avoiding scheduling delays.
Guide to optimizing network requests in iOS apps using Xcode Simulator, proxies, and AI agents for better performance.
RocketSim 15 adds VoiceOver Navigator and post-editor for Xcode simulator recordings, boosting iOS developer productivity.
Guide to optimizing Xcode build performance using new Agent Skills, covering clean/incremental builds and caching.
