Do communication between Reflex frontend and Yesod backend using websocket protocol.
This will compile and run the yesod server on port 3000
cd backend; stack build; stack exec reflex-yesod-websockets-backend
For compiling front-end use the script from reflex-platform
/path/to/reflex-platform/work-on ghcjs ./frontend
cd frontend; cabal configure --ghcjs && cabal build
Then open the generated index.html in browser.
Note that if you open localhost:3000 directly in browser then it will use the page from yesod instead, which essentially does the same work as reflex frontend.
Yesod code has been taken from (https://github.com/yesodweb/yesod/blob/master/yesod-websockets/sample.hs)
Reflex code from (https://github.com/reflex-frp/reflex-examples/blob/master/websocket-echo/src/Main.hs)