Use when designing or building native macOS applications with SwiftUI or AppKit. Triggers on menu bar structure, keyboard shortcuts, multi-window behavior, Liquid Glass design system, macOS Tahoe/Sequoia, sidebar navigation, toolbar design, app icons, SF Symbols, or making an app feel like a "good Mac citizen."
View on GitHubpetekp/agent-skills
explainer
January 25, 2026
Select agents to install to:
npx add-skill https://github.com/petekp/agent-skills/blob/main/skills/macos-app-design/SKILL.md -a claude-code --skill macos-app-designInstallation paths:
.claude/skills/macos-app-design/# macOS App Design & Development Guide for designing and implementing native-feeling, "good Mac citizen" apps: fast, elegant, accessible, and deeply integrated with macOS workflows. ## Two Rules That Beat Everything Else 1. **Prefer system components and conventions** over bespoke UI—fastest path to "feels right on Mac" 2. **If you customize bars, backgrounds, borders, or control chrome**: stop and justify it ## Quick Reference: Mac Citizen Checklist | Area | Requirement | |------|-------------| | **Menu Bar** | Standard layout (App/File/Edit/View/Window/Help), ⌘, for Settings | | **Keyboard** | Every primary command reachable via keyboard, standard shortcuts work | | **Windows** | Resize fluidly, support multiple windows, respect fullscreen/minimize | | **Sidebars** | Top-level navigation, scannable items, content extends behind | | **Toolbars** | Group by function/frequency, demote secondary to "more" menu | | **Text** | Use system text components, standard editing behaviors | | **Accessibility** | VoiceOver labels, full keyboard navigation, Reduced Motion support | ## Liquid Glass Quick Rules **Do:** - Use for navigation/controls layer (toolbars, sidebars, bars) - Let system components provide built-in behaviors **Don't:** - Apply to content layer (tables, lists, document content) - Stack "glass on glass" ## App Archetypes Identify your app type first: - **Document-based**: Files as primary units (open/save/duplicate) - **Library + editor**: Sidebar lists items, detail in main area - **Utility**: Single window, optional menu bar - **Menu-bar app**: Lives in menu bar, minimal UI - **Pro tool**: Dense, power-user workflows ## Deliverables Before Building 1. **App archetype** identified 2. **Information architecture** (sidebar structure, navigation, window model) 3. **Command map** (menus + keyboard shortcuts for every major feature) 4. **State + data model** (persistence, undo/redo, concurrency) 5. **Accessibility plan** (VoiceOver, keyboard, contrast,