WebSocket Engineer Skill Overview Real-time, bidirectional communication systems using WebSockets and related protocols. Covers protocol fundamentals, server implementation, authentication, scaling, fault tolerance, and browser client patterns. Protocol Fundamentals Server Implementation — ws (Node.js) Authentication Patterns Horizontal Scaling with Redis Socket.IO (Higher-Level Abstraction) Browser Client Server-Sent Events (SSE) — Unidirectional Alternative Message Protocol Design Rate Limiting Observability Security - Always use (TLS) in production — plain is MITM-vulnerable - Authenticate…