diff --git a/CHANGELOG.md b/CHANGELOG.md
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -27,3 +27,8 @@
 ## 0.1.3.3 -- 2020-05-13
 
 * added comment
+
+## 0.1.3.4 -- 2020-05-13
+
+* add type signature for hyloM' and chronoM.
+
diff --git a/monadic-recursion-schemes.cabal b/monadic-recursion-schemes.cabal
--- a/monadic-recursion-schemes.cabal
+++ b/monadic-recursion-schemes.cabal
@@ -4,7 +4,7 @@
 -- http://haskell.org/cabal/users-guide/
 
 name:                monadic-recursion-schemes
-version:             0.1.3.3
+version:             0.1.3.4
 synopsis:            Recursion Schemes for Monadic version.
 description:         Yet another recursion schemes for monadic style, depends on recursion-schemes.
 homepage:            https://github.com/cutsea110/monadic-recursion-schemes.git
diff --git a/src/Data/Functor/Foldable/Monadic.hs b/src/Data/Functor/Foldable/Monadic.hs
--- a/src/Data/Functor/Foldable/Monadic.hs
+++ b/src/Data/Functor/Foldable/Monadic.hs
@@ -6,6 +6,7 @@
 {-# LANGUAGE FlexibleContexts #-}
 {-# LANGUAGE AllowAmbiguousTypes #-}
 {-# LANGUAGE ScopedTypeVariables #-}
+{-# LANGUAGE TypeFamilyDependencies #-}
 module Data.Functor.Foldable.Monadic
   ( cataM, anaM
   , paraM, apoM
@@ -114,9 +115,12 @@
 hyloM phi psi = h
   where h = phi <=< mapM h <=< psi
 
--- FIXME: I couldn't compile with this type signature.
 -- | hylomorphism on combination variant of ana to cata
-hyloM' phi psi = cataM phi <=< anaM psi
+hyloM' :: forall m t a b. (Monad m, Traversable (Base t), Recursive t, Corecursive t)
+       => (Base t b -> m b)   -- ^ algebra
+       -> (a -> m (Base t a)) -- ^ coalgebra
+       -> a -> m b
+hyloM' phi psi = (cataM phi :: t -> m b) <=< (anaM psi :: a -> m t)
 
 -- | metamorphism on recursive variant
 metaM :: (Monad m, Traversable (Base t), Recursive s, Corecursive t, Base s ~ Base t)
@@ -143,9 +147,12 @@
         g (Pure  a) = psi a
         g (Free fb) = return fb
 
--- FIXME: I couldn't compile with this type signature.
 -- | chronomorphism on combination variant of futu to hist
-chronoM phi psi = histoM phi <=< futuM psi
+chronoM :: forall m t a b. (Monad m, Traversable (Base t), Recursive t, Corecursive t)
+        => (Base t (Cofree (Base t) b) -> m b) -- ^ algebra
+        -> (a -> m (Base t (Free (Base t) a))) -- ^ coalgebra
+        -> a -> m b
+chronoM phi psi = (histoM phi :: t -> m b) <=< (futuM psi :: a -> m t)
 
 cochronoM :: (Monad m, Corecursive c, Traversable (Base c), Traversable (Base t), Recursive t)
           => (Base t (Cofree (Base t) a) -> m a) -- ^ algebra