diff --git a/pinboard.cabal b/pinboard.cabal
--- a/pinboard.cabal
+++ b/pinboard.cabal
@@ -1,5 +1,5 @@
 name:                pinboard
-version:             0.8.9
+version:             0.8.10
 synopsis:            Access to the Pinboard API
 license:             MIT
 license-file:        LICENSE
diff --git a/src/Pinboard/Client.hs b/src/Pinboard/Client.hs
--- a/src/Pinboard/Client.hs
+++ b/src/Pinboard/Client.hs
@@ -126,7 +126,7 @@
     responseBody r <$ checkStatusCodeResponse r
 
 runPinboardSingleJson
-    :: (MonadIO m, FromJSON a)
+    :: (Functor m, MonadIO m, FromJSON a)
     => PinboardConfig       
     -> PinboardRequest
     -> m (Either PinboardError a)
@@ -155,7 +155,7 @@
 buildReq url = do
   req <- liftIO $ parseUrl $ "https://api.pinboard.in/v1/" <> url
   return $ req 
-    { requestHeaders = [("User-Agent","pinboard.hs/0.8.9")]
+    { requestHeaders = [("User-Agent","pinboard.hs/0.8.10")]
     , checkStatus = \_ _ _ -> Nothing
     }