audit-swift-performance

Scan for performance anti-patterns at the Swift language level — overhead from ARC, unnecessary allocations, and code that prevents the optimizer from specializing generics.

What This Command Does

Launches the swift-performance-analyzer agent to surface Swift-language performance issues that show up in Time Profiler and Allocations traces.

What It Checks

1. ARC issues – excessive retain/release in hot paths, @inlinable opportunities, missing consume/borrow ownership
2. Allocation patterns – Array.append in tight loops without reserveCapacity, repeated String concatenation, unnecessary boxing
3. Generic specialization – public generics without @inlinable that compile to slow witness-table dispatch
4. Existential overhead – any Protocol parameters where some Protocol would specialize
5. COW pitfalls – copy-on-write types being mutated through multiple references, defeating value semantics

Related Agent

• swift-performance-analyzer – The agent that powers this command