react-to-ios

React to iOS: Feature Parity Implementation

Use React/React Native code as the reference to implement the equivalent native iOS feature. Not a literal translation - understand what the React code does, then implement it idiomatically for iOS.

Use this when:

• Porting a feature from React/React Native to native iOS
• React is the "source of truth" for a feature
• Building native iOS alternatives to web components
• Migrating from React Native to native Swift

Key Principle

React Code → Understand Feature → Match iOS Codebase Patterns → Implement
                 (what)                  (how it's done here)

Preserved: Feature behavior, data structure shapes, business logic, user flows, API contracts Adapted: Language idioms, frameworks, UI patterns to match the iOS codebase

---

Common Mappings Reference

React/React Native	iOS/Swift Equivalent
useState	@State / @Published
useEffect	.onAppear / .task / viewDidLoad
useContext	Environment objects / Dependency injection
useMemo / useCallback	Computed properties / lazy vars
useReducer	State machine / Combine
Props	Init parameters / Bindings
View / div	SwiftUI View / UIKit UIView
Text	Text / UILabel
Image	Image / UIImageView
ScrollView	ScrollView / UIScrollView
FlatList	List / LazyVStack / UITableView
TouchableOpacity	Button / tap gestures
TextInput	TextField / UITextField
StyleSheet	SwiftUI modifiers / UIKit constraints
fetch / axios	URLSession / async-await
Redux / Zustand	Combine / SwiftUI state / TCA
React Navigation	NavigationStack / UINavigationController
React Query / SWR	Async/await patterns / Combine
Styled Components	View modifiers / custom ViewModifiers
Context Providers	@EnvironmentObject / DI containers

---

Workflow

Step 0: Gather Context

Ask the user for both pieces of information:

To port a feature from React to iOS, I need:

1. PATH TO REACT CODEBASE (source of truth)
   Where is the React/React Native project located?
   Example: /path/to/react-app or ../react-native-app

2. FEATURE TO IMPLEMENT
   What feature or component should I port?
   Example: "UserProfile component" or "the checkout flow" or "src/components/Dashboard"

Assumptions:

• Current working directory = iOS codebase (target)
• User provides path to React codebase (source)

If the user already provided this info, proceed. Otherwise, ask.

Step 1: Locate the React Feature

Navigate to the React codebase path and find the relevant files:

1. Go to the React path provided
2. Find files related to the feature (components, hooks, stores, utils)
3. Read and understand the implementation

Files to look for:

• Component files (.tsx, .jsx, .js)
• Custom hooks (use*.ts)
• State management (Redux slices, Zustand stores, Context)
• API services
• Types/interfaces (.ts, .d.ts)
• Styles (CSS modules, styled-components, StyleSheet)

Step 2: Analyze the React Code

Thoroughly understand:

Aspect	What to Extract
Feature Behavior	What does this feature do? User-facing functionality
Component Structure	Component hierarchy, props, composition patterns
State Management	useState, useReducer, Redux, Context usage
Side Effects	useEffect patterns, data fetching, subscriptions
Business Logic	Validations, transformations, calculations
API Contracts	Network calls, request/response shapes
UI Flow	Screens, navigation, user interactions
Edge Cases	Error handling, loading states, empty states

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
                  REACT FEATURE ANALYSIS
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

## Feature: [Name]

### What It Does
[User-facing description]

### Component Structure
[Component hierarchy and relationships]

### Props & State
[Key props, state variables, their purposes]

### Side Effects
[What useEffect/data fetching does]

### Business Logic
[Core logic summary]

### API Calls
[Endpoints, request/response shapes]

### UI Flow
[Screens, navigation, interactions]

### Edge Cases Handled
- [Case 1]
- [Case 2]

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

Step 3: Analyze iOS Codebase Patterns

Before implementing, understand how THIS iOS codebase does things:

1. Check if .claude/codebase-style.md exists - If yes, use it and skip manual analysis
2. Find similar features in the codebase
3. Note the patterns used:
   • Architecture pattern (MVVM, MVC, TCA, VIPER)
   • UI framework (SwiftUI vs UIKit)
   • State management approach
   • Networking approach
   • Dependency injection
   • File/folder organization
   • Naming conventions

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
                 iOS CODEBASE PATTERNS
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

Style Guide: [Found / Not found]

Patterns observed from existing code:
- Architecture: [MVVM / MVC / TCA / VIPER / etc.]
- UI Framework: [SwiftUI / UIKit / Mixed]
- State: [how state is managed]
- Networking: [how API calls are made]
- DI: [how dependencies are injected]
- Navigation: [how navigation works]

Similar features to reference:
- [Feature 1]: [path]
- [Feature 2]: [path]

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

Step 4: Create Implementation Plan

Map the React feature to iOS equivalents using the patterns from Step 3:

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
                  IMPLEMENTATION PLAN
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

## Files to Create

| # | File | Purpose | React Equivalent |
|---|------|---------|------------------|
| 1 | [path matching codebase conventions] | [purpose] | [React file] |
| 2 | ... | ... | ... |

## Key Mappings

| React Concept | iOS Equivalent (matching codebase patterns) |
|---------------|---------------------------------------------|
| [React thing] | [iOS equivalent as done in this codebase] |
| ... | ... |

## State Migration

| React State | iOS State Management |
|-------------|---------------------|
| [useState/Redux/etc.] | [How it maps to iOS patterns] |

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

Step 5: Implement

Create the iOS implementation:

• Match the codebase's existing patterns exactly
• Use the same architecture, UI patterns, state management as other features
• Follow the same naming conventions
• Keep data structure shapes equivalent for API compatibility
• Translate React patterns to idiomatic Swift/SwiftUI

Pattern Translation Tips:

React Pattern	iOS Implementation
Component with props	View with init parameters or @Binding
useState + setState	@State property with direct mutation
useEffect on mount	.onAppear or .task modifier
useEffect with deps	.onChange(of:) modifier
useEffect cleanup	.onDisappear or task cancellation
Conditional rendering	if/else or @ViewBuilder
List mapping	ForEach
Event handlers	Action closures or Bindings
CSS/StyleSheet	SwiftUI modifiers or custom ViewModifier

⚠️ IMPORTANT: After creating each .swift file, register it with Xcode:

ruby ${CLAUDE_PLUGIN_ROOT}/skills/add-to-xcode/scripts/add_to_xcode.rb <filepath>

Without this step, files won't appear in Xcode or compile. See the add-to-xcode skill.

Step 6: Copy Assets (if needed)

If the feature uses assets, offer to copy them:

Assets that may need to be copied:

• Images, icons (convert to Asset Catalog format)
• Colors (convert to Color Sets)
• Fonts
• Lottie animations
• Sounds

If assets are needed and the user wants them copied, use file operations to transfer and convert them appropriately for iOS.

Step 7: Report Results

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
                 REACT → iOS COMPLETE
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

## Feature: [Name]

### Files Created

| File | Purpose |
|------|---------|
| [path] | [description] |

### Feature Parity Checklist

- [x] Core functionality matches React
- [x] Data structures equivalent
- [x] State management properly translated
- [x] Side effects handled
- [x] Error handling preserved
- [x] Loading states preserved
- [x] Edge cases handled
- [x] Matches iOS codebase patterns

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

---

Triggers

"react to ios"
"react native to ios"
"convert from react"
"port this react component to swift"
"implement this react feature for ios"
"ios version of this react code"
"native ios from react native"
"migrate react native to swift"

---

Integration with style-guide

Recommended: Run the style-guide skill on the iOS codebase first.

style guide    ← Run this first on iOS codebase
react to ios   ← Then run this

This generates .claude/codebase-style.md which this skill will automatically reference.

If style guide exists:

• Skip manual pattern analysis (Step 3)
• Reference the documented patterns directly
• Ensure perfect consistency with existing code

If no style guide:

• This skill will analyze patterns manually (Step 3)
• Consider running style-guide first for better results

---

Tips

1. Don't translate literally - Understand the feature, then implement idiomatically
2. Match the codebase - Use the same patterns as existing iOS code
3. Keep data shapes equivalent - API compatibility matters
4. Handle paradigm differences - React is declarative but different from SwiftUI
5. Verify feature parity - Same behavior, not same code
6. Consider lifecycle differences - React component lifecycle ≠ SwiftUI view lifecycle
7. State is different - React re-renders on state change; SwiftUI uses property wrappers
8. Navigation differs - React Router/Navigation vs NavigationStack patterns