diff --git a/Numeric/AD/Internal/Classes.hs b/Numeric/AD/Internal/Classes.hs
--- a/Numeric/AD/Internal/Classes.hs
+++ b/Numeric/AD/Internal/Classes.hs
@@ -35,6 +35,7 @@
 infixl 6 +!, -!, <+>
 infix 4 ==!
 
+
 class Iso a b where
     iso :: f a -> f b
     osi :: f b -> f a
@@ -199,7 +200,7 @@
         abs1          = lift1 abs signum1
         signum1       = lift1 signum (const zero)
         fromRational1 = lift . fromRational
-        (/!)          = lift2_ (/) $ \a x y -> (recip1 y, x *! negate1 (square1 a))
+        x /! y        = x *! recip1 y
         recip1        = lift1_ recip (const . negate1 . square1)
 
         pi1       = lift pi
@@ -209,7 +210,7 @@
         sqrt1     = lift1_ sqrt (\z _ -> recip1 (lift 2 *! z))
         (**!)     = lift2_ (**) (\z x y -> (y *! z /! x, z *! log1 x)) -- error at 0 ** n
         sin1      = lift1 sin cos1
-        cos1      = lift1 cos $ \x -> negate1 (sin1 x)
+        cos1      = lift1 cos $ negate1 . sin1
         tan1 x    = sin1 x /! cos1 x
         asin1     = lift1 asin $ \x -> recip1 (sqrt1 (one -! square1 x))
         acos1     = lift1 acos $ \x -> negate1 (recip1 (sqrt1 (one -! square1 x)))
diff --git a/Numeric/AD/Internal/Stream.hs b/Numeric/AD/Internal/Stream.hs
--- a/Numeric/AD/Internal/Stream.hs
+++ b/Numeric/AD/Internal/Stream.hs
@@ -23,7 +23,7 @@
 import Data.Foldable
 import Data.Traversable
 import Data.Data (Data(..), mkDataType, DataType, mkConstr, Constr, constrIndex, Fixity(Infix))
-import Data.Typeable (Typeable1(..), Typeable(..), TyCon, mkTyCon, mkTyConApp, gcast1)
+import Data.Typeable (Typeable1(..), TyCon, mkTyCon, mkTyConApp, gcast1)
 import Numeric.AD.Internal.Comonad
 
 infixl 3 :<
@@ -31,8 +31,6 @@
 data Stream f a = a :< f (Stream f a)
 
 deriving instance (Show a, Show (f (Stream f a))) => Show (Stream f a)
-
--- TODO: Data, Typeable
 
 instance Functor f => Functor (Stream f) where
     fmap f (a :< as) = f a :< fmap f <$> as
diff --git a/Numeric/AD/Internal/Tensors.hs b/Numeric/AD/Internal/Tensors.hs
--- a/Numeric/AD/Internal/Tensors.hs
+++ b/Numeric/AD/Internal/Tensors.hs
@@ -22,7 +22,7 @@
 import Data.Foldable
 import Data.Traversable
 import Data.Monoid
-import Data.Typeable (Typeable1(..), Typeable(..), TyCon, mkTyCon, mkTyConApp)
+import Data.Typeable (Typeable1(..), TyCon, mkTyCon, mkTyConApp)
 import Numeric.AD.Internal.Comonad
 import Numeric.AD.Internal.Stream
 
diff --git a/ad.cabal b/ad.cabal
--- a/ad.cabal
+++ b/ad.cabal
@@ -1,5 +1,5 @@
 name:         ad
-version:      0.44.3
+version:      0.44.4
 license:      BSD3
 license-File: LICENSE
 copyright:    (c) Edward Kmett 2010,