This library allows you to write WebSocket-capable servers.

An example server:
https://github.com/jaspervdj/websockets/blob/master/example/server.lhs

An example client:
https://github.com/jaspervdj/websockets/blob/master/example/client.hs

See also:
* The specification of the WebSocket protocol:
  http://www.whatwg.org/specs/web-socket-protocol/
* The JavaScript API for dealing with WebSockets:
  http://www.w3.org/TR/websockets/