axiom▌

Comprehensive guide to writing reliable, maintainable UI tests with XCUITest.

Use when:

You MUST use this skill for ANY data persistence, database, axiom-storage, CloudKit, or serialization work.

You MUST use this skill for ANY build, environment, or Xcode-related issue before debugging application code.

Purpose: Guide robust, testable in-app purchase implementation StoreKit Version: StoreKit 2 iOS Version: iOS 15+ (iOS 18.4+ for latest features) Xcode: Xcode 13+ (Xcode 16+ recommended) Context: WWDC 2025-241, 2025-249, 2023-10013, 2021-10114

SwiftUI debugging falls into three categories, each with a different diagnostic approach:

SwiftUI's navigation APIs provide data-driven, programmatic navigation that scales from simple stacks to complex multi-column layouts. Introduced in iOS 16 (2022) with NavigationStack and NavigationSplitView, evolved in iOS 18 (2024) with Tab/Sidebar unification, and refined in iOS 26 (2025) with Liquid Glass design.

Core Principle: Optimize Swift code by understanding language-level performance characteristics—value semantics, ARC behavior, generic specialization, and memory layout—to write fast, efficient code without premature micro-optimization.

Swift Testing is Apple's modern testing framework introduced at WWDC 2024. It uses Swift macros (@Test, #expect) instead of naming conventions, runs tests in parallel by default, and integrates seamlessly with Swift concurrency.

You MUST use this skill for ANY accessibility work including VoiceOver, Dynamic Type, color contrast, and WCAG compliance.