unetworking/uwebsockets

uWebSockets is a high-performance web server library written in C and C++ that handles both standard HTTP requests and real-time WebSocket connections. The problem it solves is simple: most web servers trade speed for simplicity, but uWebSockets is engineered to be so fast that it can handle encrypted TLS 1.3 messaging quicker than many other servers can handle unencrypted traffic. It is used in production by some of the world's largest cryptocurrency exchanges, processing trade volumes of billions of dollars every day. At its core, the library provides a URL router, think of it as a traffic director that maps incoming requests to the right handler, along with built-in publish/subscribe features for WebSockets, which are the persistent, two-way connections that power live chats, price feeds, and multiplayer games. It supports wildcard routes and URL parameters, so you can match patterns like /user/:id without extra tooling. The architecture builds on a companion library called uSockets, which handles low-level networking, and lets you swap out cryptography and event-loop backends via compile flags, choosing from OpenSSL, WolfSSL, libuv, ASIO, or the raw OS kernel. You would reach for uWebSockets when building anything that demands extremely high throughput and low latency under real load, live trading platforms, real-time dashboards, multiplayer backends, or high-volume chat systems. It also integrates with Node.js through a sibling project called uWebSockets.js, making it accessible to JavaScript developers who want native-level speed without writing C++ themselves.