Request-reply service in F#

(*
Hello World server
Connects REP socket to tcp://*:5560
Expects "Hello" from client, replies with "World"
*)

#r @"bin/fszmq.dll"
open fszmq
open fszmq.Context
open fszmq.Socket

#load "zhelpers.fs"

let main () =
use context = new Context(1)

// socket to talk to clients
use responder = rep context
"tcp://localhost:5560" |> connect responder

while true do
// wait for next request from client
let message = s_recv responder
printfn "Received request: [%s]" message

// do some 'work'
sleep 1

// send reply back to client
"World" |> s_send responder

// we never get here but clean up anyhow
EXIT_SUCCESS

main ()