ios-performance-profiler

name	ios-performance-profiler
description	Identifies potential performance bottlenecks in SwiftUI code including expensive view updates, unnecessary redraws, and memory issues. Use when code involves lists, animations, complex UI, or when the user asks about performance optimization.

Performance Profiler

Checklist

View Redraws

• Views only redraw when dependencies change
• @State properly scoped
• Stable view identity (no random IDs)

Lists

• Use List not ScrollView + VStack for large data
• Stable Identifiable IDs
• Lightweight row views

Memory

• No retain cycles ([weak self] in closures)
• @StateObject for owned objects
• Image caching for remote images

Body Computation

• No heavy work in view body
• Pre-compute expensive operations

Quick Wins

Issue	Fix
Parent redraws	Extract stable child views
Expensive body	Pre-compute or cache
Unstable IDs	Use UUID in Identifiable
Retain cycle	[weak self]
Broad animation	Scope to specific views

Debug

let _ = Self._printChanges() // In view body

Severity

• 🔴 Critical: Visible lag, leaks
• 🟡 Moderate: Noticeable impact
• 🟢 Minor: Optimization opportunity