# React 19 Implementation Standards ## Current Status: NOT IMPLEMENTED The codebase uses React 19.1.1 but implements ZERO React 19 features. This is a significant gap. This might be OK if the features aren't needed, are complex or costly, or there is a better way that doesn't violate react standard approaches. ## Required React 19 Features to Implement ### 1. Actions for Form Handling Replace manual form state management with React 19 Actions: ```typescript // ❌ CURRENT - Manual state management const [loading, setLoading] = useState(false); const [error, setError] = useState(null); const handleSubmit = async (e) => { setLoading(true); try { await submitForm(e); } catch (err) { setError(err); } finally { setLoading(false); } }; // ✅ REACT 19 - Actions const [state, submitAction] = useActionState(async (prevState, formData) => { // Action automatically handles loading/error states return await submitForm(formData); }, initialState); ``` ### 2. useOptimistic for Theme Previews Implement optimistic updates for theme switching: ```typescript // ✅ IMPLEMENT function ThemePreview({ currentTheme }) { const [optimisticTheme, setOptimisticTheme] = useOptimistic( currentTheme, (currentTheme, optimisticValue) => ({ ...currentTheme, ...optimisticValue }) ); const switchTheme = async (newTheme) => { setOptimisticTheme(newTheme); // Immediate UI update await saveTheme(newTheme); // Actual save }; } ``` ### 3. Modern Context Syntax Replace Provider wrapper with direct Context rendering: ```typescript // ❌ OLD // ✅ REACT 19 ``` ### 4. Error Boundaries with Actions Implement error boundaries that work with Actions: ```typescript // ✅ IMPLEMENT class ThemeErrorBoundary extends React.Component { static getDerivedStateFromError(error) { return { hasError: true, error }; } componentDidCatch(error, errorInfo) { // Log to error reporting service console.error('Theme loading error:', error, errorInfo); } } ``` ## Implementation Priority ### HIGH PRIORITY 1. **Theme selection Actions** - Replace manual form handling 2. **Error boundaries** - Add proper error handling 3. **useOptimistic for theme previews** - Better UX ### MEDIUM PRIORITY 1. **Context syntax modernization** - Update provider patterns 2. **Form Actions for theme creation** - When that feature is added 3. **Server Actions integration** - If backend is added ### LOW PRIORITY 1. **Preloading optimization** - Use React 19 preloading APIs 2. **Streaming SSR** - If SSR is implemented 3. **Advanced concurrent features** - As needed ## Migration Strategy 1. Start with theme selection Actions (highest impact) 2. Add error boundaries for robustness 3. Implement optimistic updates for better UX 4. Gradually modernize Context usage 5. Add advanced features as needed ## Resources - [React 19 Actions Documentation](https://react.dev/reference/react/useActionState) - [useOptimistic Hook](https://react.dev/reference/react/useOptimistic) - [Error Boundaries](https://react.dev/reference/react/Component#catching-rendering-errors-with-an-error-boundary)