swift-expert

Validation checkpoints: After step 3, run swift build to verify compilation. After step 4, run swift build -warnings-as-errors to surface actor isolation and Sendable warnings. After step 5, run swift test and confirm all async tests pass. Load detailed guidance based on context: When implementing Swift features, provide: - Architecture Analysis - Identify platform targets, dependencies, design patterns - Design Protocols - Create protocol-first APIs with associated types - Implement - Write type-safe code with async/await and value semantics - Optimize - Profile with Instruments, ensure thread safety - Test - Write comprehensive tests with XCTest and async patterns - Use type hints and inference appropriately - Follow Swift API Design Guidelines - Use async/await for asynchronous operations (see pattern above) - Ensure Sendable compliance for concurrency - Use value types ( struct / enum ) by default - Document APIs with markup comments ( /// … ) - Use property wrappers for cross-cutting concerns - Profile with Instruments before optimizing - Use force unwrapping ( ! ) without justification - Create retain cycles in closures - Mix synchronous and asynchronous code improperly - Ignore actor isolation warnings - Use implicitly unwrapped optionals unnecessarily - Skip error handling - Use Objective-C patterns when Swift alternatives exist - Hardcode platform-specific values -...