useActionState usage

useFormStatus in child

useOptimistic update

'use client' directive

'use server' directive

form action prop

TypeScript types

Error state handling

Pending state disabled

Suspense boundary

No inline JSX functions

Semantic HTML

Virtualization library

React.memo on list item

Stable keys

No inline JSX functions

useCallback for handlers

useTransition for filter

lazy + Suspense splitting

useMemo for derived data

TypeScript types

Lifted static objects

Cleanup in effects

Zustand store created

Zustand persist middleware

Zustand typed store

useQuery for data fetching

staleTime configured

useMutation for writes

invalidateQueries after mutation

QueryClientProvider

Loading/error states

TypeScript throughout

Functional state updates

No direct state mutation

AbortController in fetch hook

Cancelled flag in async effect

useDebounce cleanup

useLocalStorage SSR guard

TypeScript generics

Effect dependency arrays

No unnecessary memoization

Loading and error states

TypeScript strict types

tsc typecheck log

No inline JSX functions

ErrorBoundary stays class

HOC replaced by custom hook

Render prop replaced by custom hook

componentDidMount to useEffect []

componentDidUpdate to useEffect [dep]

componentWillUnmount to cleanup

Separate useState slices

Functional state update

Effect cancellation

TypeScript types preserved

No forwardRef used

Migration notes present

MSW server setup

MSW handler imports

userEvent.setup() usage

getByRole as first choice

renderHook for hook tests

findByX for async content

renderWithProviders wrapper

Error state test

Loading state test

TypeScript test types

queryByX for absence assertion