MIT licensed by Michael Snoyman
Maintained by [email protected]
This version can be pinned in stack with:yesod-websockets-,1068

Module documentation for


The example, chat.hs, requires stm-lifted and conduit-combinators which are not dependencies of yesod-websockets. Installing the extra packages needed for the chat.hs example can be installed with the command:

$ cabal install stm-lifted conduit-combinators


Versions of yesod-websockets prior to 0.2.1 may experience session timeouts after about 30 seconds of inactivity. Refer to the patch in the websockets library which addresses this issue:


  • Removed the use of the deprecated forkPingThread and replaced it with the recommended withPingThread. #1700

  • sendClose and sendPing correctly find the Connection from WebSocketsT

    Previously, these types were incorrectly typed to look for the Connection on the m of WebSocketsT m (), and not via WebSocketsT itself. Because this made them practically impossible to use, this change is unlikely to break any existing code.

  • Minor cabal file improvements


  • Upgrade to yesod-core 1.6


  • Fix warnings


  • Allow to start websockets with custom ConnectionOptions with webSocketsOptions and webSocketsOptionsWith

  • Support for websockets 0.10


  • receiveDataMessageE and sendDataMessageE


  • Add exceptional websocket commands #772