What problem does it solve?
This Skill eliminates the guesswork in iOS performance optimization by providing a systematic, evidence-based workflow for diagnosing slow launches, UI jank, main-thread hangs, memory leaks, battery drain, slow Xcode builds, and oversized app binaries.
Core Features & Use Cases
- Profiling workflows: Route symptoms to the correct Instruments template (Time Profiler, Allocations, System Trace, Energy Log) and CLI tools like xctrace and sample.
- Memory & leak diagnosis: Identify the 6 common leak patterns (timers, observers, closures, retain cycles, view callbacks, PhotoKit requests) using Memory Graph Debugger and the CLI memory toolkit.
- SwiftUI & Swift optimization: Tune SwiftUI body re-evaluation with the @Observable macro, lazy containers, and stable identity; optimize Swift 6.2 code with InlineArray, Span, and copy-on-write best practices.
- App launch & build tuning: Reduce cold launch time below 400 ms by optimizing dyld pre-main, deferring SDK initialization, and fixing Xcode build settings for faster incremental builds.
- Binary size reduction: Apply a tiered catalogue of P1–P20 techniques with validation gates to shrink download size without sacrificing quality or security.
Quick Start
Profile your app's slow launch on a real device using the App Launch template in Instruments to identify the dominant startup phase and apply the targeted fixes from this skill.
