Node.js Internals Explained by Uncle to Nephew — Part 3: The Complete Journey (Request Lifecycle, Traffic Bursts & WebSockets)

Short summary

The final part of a Node.js internals series traces a single HTTP request from browser through OS, libuv, event loop, Express middleware, database, and back. Uses a conversational uncle-nephew format to explain how epoll notifications, middleware chains, and async database queries connect into one continuous flow. Not AI-related but solid systems-level education.

• •Traces a complete HTTP request lifecycle through Node.js internals from browser to database and back
• •Explains libuv's epoll-based notification model and how the event loop poll phase picks up ready sockets
• •Covers Express middleware chain mechanics including the next() contract and common pitfalls

Generated with AI, which can make mistakes.