diff --git a/ChangeLog.md b/ChangeLog.md
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -1,3 +1,10 @@
+Changes in 0.6.1.0
+
+  * `foldMap`, `foldMapF`, `foldMapNatF` is added
+
+  * GHC 9.0.1 compatibility
+
+
 Changes in 0.6.0.0
 
   * Type class `TyLookup` and `tyLookup` & `tyLookupF` added for lookup up field
diff --git a/Data/Vector/HFixed.hs b/Data/Vector/HFixed.hs
--- a/Data/Vector/HFixed.hs
+++ b/Data/Vector/HFixed.hs
@@ -62,6 +62,7 @@
     -- ** Folds & unfolds
   , foldr
   , foldl
+  , foldMap
   , mapM_
     -- ** Zips
   , zipWith
@@ -100,8 +101,10 @@
     -- ** Folds and unfolds
   , foldrF
   , foldlF
+  , foldMapF
   , foldrNatF
   , foldlNatF
+  , foldMapNatF
     -- ** Zips
   , zipWithF
   , zipWithNatF
@@ -311,6 +314,16 @@
 {-# INLINE foldl #-}
 foldl c f b0 = C.foldlF c (\b (Identity a) -> f b a) b0 . C.cvec
 
+-- | Monoidal fold over heterogeneuous vector
+--
+-- >>> foldMap (Proxy @Show) show (12,'c',"str")
+-- "12'c'\"str\""
+foldMap
+  :: (HVector v, ArityC c (Elems v), Monoid m)
+  => Proxy c -> (forall a. c a => a -> m) -> v -> m
+{-# INLINE foldMap #-}
+foldMap c f = C.foldMapF c (\(Identity a) -> f a) . C.cvec
+
 -- | Right fold over heterogeneous vector
 foldrF :: (HVectorF v, ArityC c (ElemsF v))
        => Proxy c -> (forall a. c a => f a -> b -> b) -> b -> v f -> b
@@ -323,6 +336,15 @@
 {-# INLINE foldlF #-}
 foldlF c f b0 = C.foldlF c f b0 . C.cvecF
 
+-- | Monoidal fold over heterogeneous vector
+--
+-- >>> foldMapF (Proxy @Show) show (mk2F (Just 1) Nothing :: HVecF '[Int,Char] Maybe)
+-- "Just 1Nothing"
+foldMapF :: (HVectorF v, ArityC c (ElemsF v), Monoid m)
+         => Proxy c -> (forall a. c a => f a -> m) -> v f -> m
+{-# INLINE foldMapF #-}
+foldMapF c f = C.foldMapF c f . C.cvecF
+
 -- | Right fold over heterogeneous vector
 foldrNatF :: (HVectorF v)
           => (forall a. f a -> b -> b) -> b -> v f -> b
@@ -335,6 +357,15 @@
 {-# INLINE foldlNatF #-}
 foldlNatF f b0 = C.foldlNatF f b0 . C.cvecF
 
+-- | Monoidal fold over heterogeneous vector
+--
+-- >>> foldMapNatF (Sum . getConst) (mk2F (Const 1) (Const 2) :: HVecF '[Char,String] (Const Int))
+-- Sum {getSum = 3}
+foldMapNatF :: (HVectorF v, Monoid m)
+            => (forall a. f a -> m) -> v f -> m
+{-# INLINE foldMapNatF #-}
+foldMapNatF f = C.foldMapNatF f . C.cvecF
+
 -- | Apply monadic action to every element in the vector
 mapM_ :: (HVector v, ArityC c (Elems v), Applicative f)
       => Proxy c -> (forall a. c a => a -> f ()) -> v -> f ()
@@ -687,8 +718,9 @@
 -- >>> import Prelude (Int,Double,String,Char,IO,(++),Maybe(..))
 -- >>> import Prelude (Show(..),Read(..),read,Num(..),Monoid(..))
 -- >>> import Prelude (print)
--- >>> import Data.Complex (Complex(..))
--- >>> import Data.Monoid  (Sum(..),Product(..))
--- >>> import Data.Maybe   (fromMaybe)
+-- >>> import Control.Applicative     (Const(..))
+-- >>> import Data.Complex            (Complex(..))
+-- >>> import Data.Monoid             (Sum(..),Product(..))
+-- >>> import Data.Maybe              (fromMaybe)
 -- >>> import Data.Vector.HFixed.HVec (HVec,HVecF)
--- >>> import GHC.Generics (Generic)
+-- >>> import GHC.Generics            (Generic)
diff --git a/Data/Vector/HFixed/Class.hs b/Data/Vector/HFixed/Class.hs
--- a/Data/Vector/HFixed/Class.hs
+++ b/Data/Vector/HFixed/Class.hs
@@ -576,10 +576,10 @@
 instance Index n xs => Index ('S n) (x : xs) where
   type ValueAt  ('S n) (x : xs)   = ValueAt n xs
   type NewElems ('S n) (x : xs) a = x : NewElems n xs a
-  getF    _   = constFun $ getF    (Proxy @ n)
-  putF    _ x = stepTFun $ putF    (Proxy @ n) x
-  lensF   _ f = stepTFun $ lensF   (Proxy @ n) f
-  lensChF _ f = stepTFun $ lensChF (Proxy @ n) f
+  getF    _   = constFun $ getF    (Proxy @n)
+  putF    _ x = stepTFun $ putF    (Proxy @n) x
+  lensF   _ f = stepTFun $ lensF   (Proxy @n) f
+  lensChF _ f = stepTFun $ lensChF (Proxy @n) f
   {-# INLINE getF    #-}
   {-# INLINE putF    #-}
   {-# INLINE lensF   #-}
diff --git a/Data/Vector/HFixed/Cont.hs b/Data/Vector/HFixed/Cont.hs
--- a/Data/Vector/HFixed/Cont.hs
+++ b/Data/Vector/HFixed/Cont.hs
@@ -51,8 +51,10 @@
     -- ** Folds and unfolds
   , foldlF
   , foldrF
+  , foldMapF
   , foldlNatF
   , foldrNatF
+  , foldMapNatF
   , unfoldrF
     -- ** Replicate variants
   , replicateF
@@ -239,7 +241,7 @@
     (\(T_List f) (Identity a) -> T_List (f . Cons a))
     (\(T_List f)              -> f Nil)
     (T_List id)
-  inspect = runContVecF . apply step
+  inspect f = runContVecF (apply step f)
     where
       step :: VecList (a : as) -> (Identity a, VecList as)
       step (Cons a xs) = (Identity a, xs)
@@ -292,6 +294,28 @@
 ----------------------------------------------------------------
 -- Folds
 ----------------------------------------------------------------
+
+-- | Monoidal fold over vector
+foldMapNatF
+  :: (Monoid m, Arity xs)
+  => (forall a. f a -> m) -> ContVecF xs f -> m
+{-# INLINE foldMapNatF #-}
+foldMapNatF f v
+  = inspectF v
+  $ accum (\(Const m) a -> Const (m <> f a))
+          (\(Const m)   -> m)
+          (Const mempty)
+
+-- | Monoidal fold over vector
+foldMapF
+  :: (Monoid m, ArityC c xs)
+  => Proxy c -> (forall a. c a => f a -> m) -> ContVecF xs f -> m
+{-# INLINE foldMapF #-}
+foldMapF cls f v
+  = inspectF v
+  $ accumC cls (\(Const m) a -> Const (m <> f a))
+               (\(Const m)   -> m)
+               (Const mempty)
 
 -- | Right fold over vector
 foldrF :: (ArityC c xs)
diff --git a/Data/Vector/HFixed/HVec.hs b/Data/Vector/HFixed/HVec.hs
--- a/Data/Vector/HFixed/HVec.hs
+++ b/Data/Vector/HFixed/HVec.hs
@@ -53,7 +53,7 @@
     (\(T_con _ box)   -> HVecF $ runBox len box)
     (T_con 0 (Box $ \_ -> return ()))
     where
-    len = arity (Proxy @ xs)
+    len = arity (Proxy @xs)
   {-# INLINE constructF #-}
 
 data T_insp (xs :: [*]) = T_insp Int (SmallArray Any)
@@ -80,11 +80,11 @@
   showsPrec _ v = showChar '['
                 . ( foldr (.) id
                   $ intersperse (showChar ',')
-                  $ H.foldrF (Proxy @ Show) (\x xs -> showsPrec1 0 x : xs) [] v
+                  $ H.foldrF (Proxy @Show) (\x xs -> showsPrec1 0 x : xs) [] v
                   )
                 . showChar ']'
 instance (Eq1 f, ArityC Eq xs) => Eq (HVecF xs f) where
-  v == u = getAll $ H.zipFoldF (Proxy @ Eq) (\x y -> All (eq1 x y)) v u
+  v == u = getAll $ H.zipFoldF (Proxy @Eq) (\x y -> All (eq1 x y)) v u
 instance (Ord1 f, ArityC Eq xs, ArityC Ord xs) => Ord (HVecF xs f) where
   compare = H.zipFoldF (Proxy :: Proxy Ord) compare1
 
@@ -123,13 +123,13 @@
          , ArityC Semigroup xs
 #endif
          ) => Monoid (HVec xs) where
-  mempty  = H.replicate (Proxy @ Monoid) mempty
-  mappend = H.zipWith   (Proxy @ Monoid) mappend
+  mempty  = H.replicate (Proxy @Monoid) mempty
+  mappend = H.zipWith   (Proxy @Monoid) mappend
   {-# INLINE mempty  #-}
   {-# INLINE mappend #-}
 
 instance (ArityC Semigroup xs) => Semigroup (HVec xs) where
-  (<>) = H.zipWith   (Proxy @ Semigroup) (<>)
+  (<>) = H.zipWith   (Proxy @Semigroup) (<>)
   {-# INLINE (<>) #-}
 
 instance (ArityC NFData xs) => NFData (HVec xs) where
diff --git a/Setup.hs b/Setup.hs
deleted file mode 100644
--- a/Setup.hs
+++ /dev/null
@@ -1,33 +0,0 @@
-{-# LANGUAGE CPP #-}
-{-# OPTIONS_GHC -Wall #-}
-module Main (main) where
-
-#ifndef MIN_VERSION_cabal_doctest
-#define MIN_VERSION_cabal_doctest(x,y,z) 0
-#endif
-
-#if MIN_VERSION_cabal_doctest(1,0,0)
-
-import Distribution.Extra.Doctest ( defaultMainWithDoctests )
-main :: IO ()
-main = defaultMainWithDoctests "doctests"
-
-#else
-
-#ifdef MIN_VERSION_Cabal
--- If the macro is defined, we have new cabal-install,
--- but for some reason we don't have cabal-doctest in package-db
---
--- Probably we are running cabal sdist, when otherwise using new-build
--- workflow
-#warning You are configuring this package without cabal-doctest installed. \
-         The doctests test-suite will not work as a result. \
-         To fix this, install cabal-doctest before configuring.
-#endif
-
-import Distribution.Simple
-
-main :: IO ()
-main = defaultMain
-
-#endif
diff --git a/fixed-vector-hetero.cabal b/fixed-vector-hetero.cabal
--- a/fixed-vector-hetero.cabal
+++ b/fixed-vector-hetero.cabal
@@ -1,5 +1,5 @@
 Name:           fixed-vector-hetero
-Version:        0.6.0.0
+Version:        0.6.1.0
 Synopsis:       Library for working with product types generically
 Description:
   Library allow to work with arbitrary product types in generic
@@ -13,7 +13,7 @@
 Maintainer:     Aleksey Khudyakov <alexey.skladnoy@gmail.com>
 Homepage:       http://github.org/Shimuuar/fixed-vector-hetero
 Category:       Data
-Build-Type:     Custom
+Build-Type:     Simple
 extra-source-files:
   ChangeLog.md
 
@@ -22,20 +22,15 @@
      || ==8.2.2
      || ==8.4.4
      || ==8.6.5
-     || ==8.8.3
-     || ==8.10.1
+     || ==8.8.4
+     || ==8.10.2
+     || ==9.0.1
   , GHCJS ==8.4
 
 source-repository head
   type:     git
   location: http://github.com/Shimuuar/fixed-vector-hetero
 
-custom-setup
-    setup-depends:
-        base          >=4.9   && <5,
-        Cabal         >=1.10  && <3.3,
-        cabal-doctest >=1.0.6 && <1.1
-
 Library
   -- Bigger context stack needed for HVector instances for large
   -- tuples
@@ -61,8 +56,8 @@
     hs-source-dirs:   test
     default-language: Haskell2010
     build-depends:
-        base                >=4.9 && <5
-      , doctest             >=0.15 && <0.17
+        base                >=4.9  && <5
+      , doctest             >=0.15 && <0.19
       , fixed-vector        >=1.0
       , fixed-vector-hetero -any
 
diff --git a/test/doctests.hs b/test/doctests.hs
--- a/test/doctests.hs
+++ b/test/doctests.hs
@@ -1,6 +1,5 @@
 module Main where
 
-import Build_doctests (flags, pkgs, module_sources)
 import Data.Foldable  (traverse_)
 import Test.DocTest   (doctest)
 
@@ -9,4 +8,5 @@
     traverse_ putStrLn args
     doctest args
   where
-    args = flags ++ pkgs ++ module_sources
+    args = ["Data"]
+