diff --git a/src/Quasar/Async/STMHelper.hs b/src/Quasar/Async/STMHelper.hs
index 3b92b1994f02a320f34f47819aa3d3176a38994e..143cbd1421f17195033c198e486e54c745c1b109 100644
--- a/src/Quasar/Async/STMHelper.hs
+++ b/src/Quasar/Async/STMHelper.hs
@@ -33,7 +33,7 @@ startShortIO fn (TIOWorker jobQueue) exChan = do
           failAsyncVar_ resultVar $ toException $ AsyncException ex
         Right result -> putAsyncVar_ resultVar result
 
-startShortIO_ :: forall a. ShortIO a -> TIOWorker -> ExceptionChannel -> STM ()
+startShortIO_ :: ShortIO () -> TIOWorker -> ExceptionChannel -> STM ()
 startShortIO_ x y z = void $ startShortIO x y z