ios-design-system

# Airbnb iOS Design System Best Practices Opinionated, strict design system engineering for SwiftUI iOS 26 / Swift 6.2 apps. Contains 50 rules across 8 categories, prioritized by impact. Derived from Airbnb's Design Language System (DLS), Airbnb Swift Style Guide, Apple Human Interface Guidelines, and WWDC sessions. Mandates @Equatable on every view, @Observable for state, and style protocols as the primary component API. ## Mandated Architecture Alignment This skill is designed to work alongside `swift-ui-architect`. All code examples follow the same non-negotiable constraints: - Feature modules depend on `Domain` + `DesignSystem`; no direct `Data` dependency - `@Observable` for mutable UI state, `ObservableObject` / `@Published` never - `@Equatable` macro on every view - Style protocols as the primary component styling API (Airbnb DLS pattern) - Asset catalog as the source of truth for color values - Local SPM package for design system module boundary ## Scope & Relationship to Sibling Skills This skill is the **infrastructure layer** — it teaches how to BUILD the design system itself. When loaded alongside sibling skills: | Sibling Skill | Its Focus | This Skill's Focus | |---------------|-----------|-------------------| | `swift-ui-architect` | **Architecture** (modular MVVM-C, route shells, protocol boundaries) | **Design system infrastructure** (tokens, styles, governance) | | `ios-design` | **Using** design primitives (semantic colors, typography) | **Engineerin...