nextjs-fullstack

Next.js fullstack development guidelines for React 19 and Next.js 15+. Use when building Next.js applications with Feature-Sliced Design, TailwindCSS v4, ShadCN, Jotai, React Query, and Supabase integration. Covers file naming, component architecture, testing with Vitest/Playwright, UI/UX design patterns, and Toss frontend principles.