frontend-developer

React Server Components in Next.js 15 render on the server by default in the App Router, streaming HTML with Suspense boundaries for progressive loading. Use async components for data fetching and mark interactive parts with the 'use client' directive.

Define a Server Action with the 'use server' directive and call it from a form's action prop. Combine useActionState for pending states and useOptimistic to update the UI immediately before the server confirms the mutation.

Zustand offers a minimal API with no boilerplate, suiting most client state needs, while Redux Toolkit fits complex state scenarios requiring middleware, devtools, and strict patterns. For server state, TanStack Query or SWR is preferred over either.

Yes, Next.js 15 supports React 19 features including Actions, useOptimistic, useActionState, and useTransition. These hooks integrate with Server Actions to handle mutations, pending states, and optimistic UI updates natively.

Excessive re-renders usually come from unstable props, inline object or function references, or oversized context values. Apply React.memo, useMemo, and useCallback selectively, split contexts, and profile with React DevTools to locate the source.

This Skill targets web frontend work with React and Next.js. It is not suited for backend API architecture, native mobile apps outside the web stack, or pure visual design tasks without implementation requirements.