Cowboy

Cowboy is a small, fast, modern HTTP server for Erlang and OTP applications. It provides a complete HTTP stack while keeping the codebase compact and optimized for low latency and low memory usage. Cowboy supports routing, request dispatching, HTTP handlers, REST handlers, WebSocket connections, and long-lived streaming-style interactions. Because it uses Ranch for connection management, it can be embedded directly inside larger Erlang systems rather than deployed only as a separate web server. The project is well suited for real-time systems, APIs, messaging infrastructure, telecom-style applications, and fault-tolerant services that benefit from the Erlang runtime. Cowboy is a strong choice when developers need an efficient HTTP layer that fits naturally into actor-based, concurrent Erlang architectures.