Hello, I'm trying to write a simple module for the haskell web server (hws- cgi). And I would like to write a simple module that maintains some kind of state for a session. But I'm I write I cannot do this in pure Haskell ? Without adopting the sources of the Haskell web server ? I'll examplify to make it more concrete : The requestHandler function a module has to implement has this signature. requestHandler :: ServerState -> ServerRequest -> IO (Maybe Response) Let 's assume I have this implementation requestHandler st _ = return $ Just $ mkRequest where mkRequest = okResponse (serverConfig st) mkBody hs True mkBody = HereItIs " This is a test" hs = mkHeaders [contentTypeHeader "text/html"] And I would like the response to include, for example, a number indicating the number of calls that has been handled by the module. I would concider using an Mvar but I can't "remember" the mvar between requests. Am I right to assume that the interface of the requestHandler method has to be adapted ? Or that serverstate has to be adopted so that it can act as a datastore ? kind regards, Pieter