diff --git a/Data/StableMemo.hs b/Data/StableMemo.hs
--- a/Data/StableMemo.hs
+++ b/Data/StableMemo.hs
@@ -60,18 +60,16 @@
 >         map' (x:xs) = f x : go xs
 -}
 
-module Data.StableMemo (memo, memo2, memo3, (-->) (), memoPoly) where
+module Data.StableMemo (memo, memo2, memo3, memoPoly) where
 
 import Control.Applicative
 import Data.Proxy
 
 import qualified Data.StableMemo.Internal as Internal
 
-import Data.StableMemo.Internal ((-->) ())
-
 -- | Memoize a function with support for a certain form of polymorphic
 -- recursion.
-memoPoly :: (f --> g) -> (f --> g)
+memoPoly :: (forall a. f a -> g a) -> f b -> g b
 {-# NOINLINE memoPoly #-}
 memoPoly = Internal.memo (Proxy :: Proxy Internal.Strong)
 
diff --git a/Data/StableMemo/Internal.hs b/Data/StableMemo/Internal.hs
--- a/Data/StableMemo/Internal.hs
+++ b/Data/StableMemo/Internal.hs
@@ -3,7 +3,7 @@
 {-# LANGUAGE RankNTypes #-}
 {-# LANGUAGE Trustworthy #-}
 {-# LANGUAGE TypeOperators #-}
-module Data.StableMemo.Internal (Ref (..), Strong (..), (-->) (), memo) where
+module Data.StableMemo.Internal (Ref (..), Strong (..), memo) where
 
 import Data.Proxy
 import System.Mem.StableName
@@ -57,12 +57,9 @@
 unsafeFromAny :: f Any -> f a
 unsafeFromAny = unsafeCoerce
 
--- | Polymorphic memoizable function
-type f --> g = forall a. f a -> g a
-
 memo' :: Ref ref =>
-         Proxy ref -> (f --> g) -> MemoTable ref f g ->
-         Weak (MemoTable ref f g) -> (f --> g)
+         Proxy ref -> (forall a. f a -> g a) -> MemoTable ref f g ->
+         Weak (MemoTable ref f g) -> f b -> g b
 memo' _ f tbl weakTbl !x = unsafePerformIO $ do
   sn <- makeStableName $ unsafeToAny x
   lkp <- HashTable.lookup tbl sn
@@ -82,7 +79,7 @@
 tableFinalizer :: Ref ref => MemoTable ref f g -> IO ()
 tableFinalizer = HashTable.mapM_ $ finalize . unO . snd
 
-memo :: Ref ref => Proxy (ref :: * -> *) -> (f --> g) -> (f --> g)
+memo :: Ref ref => Proxy (ref :: * -> *) -> (forall a. f a -> g a) -> f b -> g b
 memo p f =
   let (tbl, weak) = unsafePerformIO $ do
         tbl' <- HashTable.new
diff --git a/Data/StableMemo/Weak.hs b/Data/StableMemo/Weak.hs
--- a/Data/StableMemo/Weak.hs
+++ b/Data/StableMemo/Weak.hs
@@ -20,7 +20,7 @@
 been computed and happens to still be in the heap, it will be
 reused, otherwise it will be recomputed.
 -}
-module Data.StableMemo.Weak (memo, memo2, memo3, (-->) (), memoPoly) where
+module Data.StableMemo.Weak (memo, memo2, memo3, memoPoly) where
 
 import Control.Applicative
 import Data.Proxy
@@ -29,11 +29,9 @@
 
 import qualified Data.StableMemo.Internal as Internal
 
-import Data.StableMemo.Internal ((-->) ())
-
 -- | Memoize a function with support for a certain form of polymorphic
 -- recursion.
-memoPoly :: (f --> g) -> (f --> g)
+memoPoly :: (forall a. f a -> g a) -> f b -> g b
 {-# NOINLINE memoPoly #-}
 memoPoly = Internal.memo (Proxy :: Proxy Weak)
 
diff --git a/stable-memo.cabal b/stable-memo.cabal
--- a/stable-memo.cabal
+++ b/stable-memo.cabal
@@ -1,5 +1,5 @@
 name:                stable-memo
-version:             0.2.4
+version:             0.3.0
 synopsis:            Memoization based on argument identity
 license:             MIT
 license-file:        LICENSE
@@ -7,7 +7,7 @@
 maintainer:          Jake McArthur <Jake.McArthur@gmail.com>
 category:            Data
 build-type:          Simple
-cabal-version:       >=1.10
+cabal-version:       >=1.18
 description:
 
   Whereas most memo combinators memoize based on equality, stable-memo
@@ -65,7 +65,7 @@
 
 library
   build-depends:       base >=4.6 && <5,
-                       hashtables >=1.0 && <1.2,
+                       hashtables >=1.0 && <1.3,
                        tagged >=0.4 && <0.8,
                        ghc-prim >=0.3 && < 0.4
   default-language:    Haskell2010
@@ -80,9 +80,9 @@
 
 source-repository head
   type:     darcs
-  location: http://patch-tag.com/r/jmcarthur/stable-memo
+  location: http://hub.darcs.net/jmcarthur/stable-memo
 
 source-repository this
   type:     darcs
   location: http://patch-tag.com/r/jmcarthur/stable-memo
-  tag:      v0.2.4
+  tag:      v0.3.0