Dez is an asynchronous network stack for Python. Its sole dependency is Registered Event Listener, which enables dez to run without libevent (a C module).

The dez library includes an asynchronous server benchmarking toolset; advanced, inotify-based static caching; XML and JSON stream parsing; Stomp, OP, HTTP, and WebSocket servers; and WebSocketProxy, which enables web application deployment on existing, unmodified TCP servers without straying from the HTML5 spec. In addition, dez offers a highly sophisticated API for implementing custom protocols, as well as a controller class that simplifies the creation of applications that require multiple servers to run in the same process.