diff --git a/.travis.yml b/.travis.yml
--- a/.travis.yml
+++ b/.travis.yml
@@ -28,6 +28,9 @@
     - env: CABALVER=1.22 GHCVER=7.10.2
       compiler: ": #GHC 7.10.2"
       addons: {apt: {packages: [cabal-install-1.22,ghc-7.10.2,alex-3.1.4,happy-1.19.5], sources: [hvr-ghc]}}
+    - env: CABALVER=1.24 GHCVER=8.0.1
+      compiler: ": #GHC 8.0.1"
+      addons: {apt: {packages: [cabal-install-1.24,ghc-8.0.1,alex-3.1.4,happy-1.19.5], sources: [hvr-ghc]}}
 
 before_install:
  - unset CC
diff --git a/CHANGELOG.markdown b/CHANGELOG.markdown
--- a/CHANGELOG.markdown
+++ b/CHANGELOG.markdown
@@ -1,3 +1,7 @@
+5.0.1
+-----
+* Removed some redundant constraints
+
 5
 -----
 * Move `Data.Functor.Kan.Rift` to `Data.Functor.Day.Curried`
diff --git a/kan-extensions.cabal b/kan-extensions.cabal
--- a/kan-extensions.cabal
+++ b/kan-extensions.cabal
@@ -1,6 +1,6 @@
 name:          kan-extensions
 category:      Data Structures, Monads, Comonads, Functors
-version:       5
+version:       5.0.1
 license:       BSD3
 cabal-version: >= 1.6
 license-file:  LICENSE
@@ -43,7 +43,7 @@
     adjunctions   >= 4.2     && < 5,
     array         >= 0.3.0.2 && < 0.6,
     base          >= 4.4     && < 5,
-    comonad       >= 4       && < 5,
+    comonad       >= 4       && < 6,
     containers    >= 0.4     && < 0.6,
     contravariant >= 1       && < 2,
     distributive  >= 0.2.2   && < 1,
diff --git a/src/Control/Monad/Co.hs b/src/Control/Monad/Co.hs
--- a/src/Control/Monad/Co.hs
+++ b/src/Control/Monad/Co.hs
@@ -128,22 +128,22 @@
 lowerCo1 :: Functor w => Co w () -> w a -> a
 lowerCo1 m = runIdentity . runCoT m . fmap (const . return)
 
-posW :: (ComonadStore s w, Monad m) => CoT w m s
+posW :: ComonadStore s w => CoT w m s
 posW = liftCoT0 pos
 
-peekW :: (ComonadStore s w, Monad m) => s -> CoT w m ()
+peekW :: ComonadStore s w => s -> CoT w m ()
 peekW s = liftCoT1 (peek s)
 
-peeksW :: (ComonadStore s w, Monad m) => (s -> s) -> CoT w m ()
+peeksW :: ComonadStore s w => (s -> s) -> CoT w m ()
 peeksW f = liftCoT1 (peeks f)
 
-askW :: (ComonadEnv e w, Monad m) => CoT w m e
+askW :: ComonadEnv e w => CoT w m e
 askW = liftCoT0 (Env.ask)
 
-asksW :: (ComonadEnv e w, Monad m) => (e -> a) -> CoT w m a
+asksW :: ComonadEnv e w => (e -> a) -> CoT w m a
 asksW f = liftCoT0 (Env.asks f)
 
-traceW :: (ComonadTraced e w, Monad m) => e -> CoT w m ()
+traceW :: ComonadTraced e w => e -> CoT w m ()
 traceW e = liftCoT1 (Traced.trace e)
 
 liftCoT0M :: (Comonad w, Monad m) => (forall a. w a -> m s) -> CoT w m s
@@ -155,7 +155,7 @@
 diter :: Functor f => a -> (a -> f a) -> Density (Cofree f) a
 diter x y = liftDensity . coiter y $ x
 
-dctrlM :: (Comonad w, Monad m) => (forall a. w a -> m (w a)) -> CoT (Density w) m ()
+dctrlM :: Monad m => (forall a. w a -> m (w a)) -> CoT (Density w) m ()
 dctrlM k = liftCoT1M (\(Density w a) -> liftM w (k a))
 
 instance (Comonad w, MonadReader e m) => MonadReader e (CoT w m) where
diff --git a/src/Data/Functor/Day/Curried.hs b/src/Data/Functor/Day/Curried.hs
--- a/src/Data/Functor/Day/Curried.hs
+++ b/src/Data/Functor/Day/Curried.hs
@@ -86,12 +86,12 @@
 {-# INLINE applied #-}
 
 -- | This is the unit of the @Day f -| Curried f@ adjunction
-unapplied :: Functor f => g a -> Curried f (Day f g) a
+unapplied :: g a -> Curried f (Day f g) a
 unapplied ga = Curried $ \ fab -> Day fab ga id
 {-# INLINE unapplied #-}
 
 -- | The universal property of 'Curried'
-toCurried :: (Functor g, Functor k) => (forall x. Day g k x -> h x) -> k a -> Curried g h a
+toCurried :: (forall x. Day g k x -> h x) -> k a -> Curried g h a
 toCurried h ka = Curried $ \gar -> h (Day gar ka id)
 {-# INLINE toCurried #-}