Frontend React.js (Hooks, component architecture) Next.js (SSR/SSG, routing, data fetching) JavaScript (ES6+) HTML5 / CSS3 Tailwind CSS / Bootstrap Responsive UI Development State Management: Zustand (stores, selectors, async actions) API Integration: REST APIs (Axios, Fetch) Backend Node.js, NestJS RESTful API Development Modular & Plugin-based Backend Architecture Realtime Systems: WebSocket, room-based messaging Event-driven Architecture Layered Architecture (Gateway, Service, Domain Events) ...