diff --git a/product-isomorphic.cabal b/product-isomorphic.cabal
--- a/product-isomorphic.cabal
+++ b/product-isomorphic.cabal
@@ -1,5 +1,5 @@
 name:                product-isomorphic
-version:             0.0.3.1
+version:             0.0.3.2
 synopsis:            Weaken applicative functor on products
 description:         Weaken applicative functor which allows only product
                      construction. Product constructions and deconstructions
@@ -14,7 +14,8 @@
 build-type:          Simple
 -- extra-source-files:
 cabal-version:       >=1.10
-tested-with:           GHC == 8.2.1
+tested-with:           GHC == 8.4.1, GHC == 8.4.2
+                     , GHC == 8.2.1, GHC == 8.2.2
                      , GHC == 8.0.1, GHC == 8.0.2
                      , GHC == 7.10.1, GHC == 7.10.2, GHC == 7.10.3
                      , GHC == 7.8.1, GHC == 7.8.2, GHC == 7.8.3, GHC == 7.8.4
@@ -35,7 +36,7 @@
   other-modules:
                      Data.Functor.ProductIsomorphic.TH.Internal
 
-  build-depends:       base <5
+  build-depends:       base >=4.5 && <5
                      , template-haskell
                      , th-data-compat
   if impl(ghc == 7.4.*)
@@ -44,6 +45,18 @@
   default-language:    Haskell2010
   ghc-options:         -Wall
 
+test-suite th
+  build-depends:         base <5
+                       , template-haskell
+                       , product-isomorphic
+
+  type:                exitcode-stdio-1.0
+  main-is:             doTH.hs
+
+  hs-source-dirs:      test
+  ghc-options:         -Wall
+
+  default-language:     Haskell2010
 
 source-repository head
   type:       git
diff --git a/src/Data/Functor/ProductIsomorphic/TH/Internal.hs b/src/Data/Functor/ProductIsomorphic/TH/Internal.hs
--- a/src/Data/Functor/ProductIsomorphic/TH/Internal.hs
+++ b/src/Data/Functor/ProductIsomorphic/TH/Internal.hs
@@ -3,7 +3,7 @@
 
 -- |
 -- Module      : Data.Functor.ProductIsomorphic.TH.Internal
--- Copyright   : 2017 Kei Hibino
+-- Copyright   : 2017-2018 Kei Hibino
 -- License     : BSD3
 --
 -- Maintainer  : ex8k.hibino@gmail.com
@@ -17,11 +17,12 @@
   reifyRecordType,
   ) where
 
+import Control.Applicative ((<|>))
 import Language.Haskell.TH
   (Q, Name, tupleTypeName, Info (..), reify,
    TypeQ, arrowT, appT, conT, varT,
-   Dec, ExpQ, conE, Con (..), TyVarBndr (..), )
-import Language.Haskell.TH.Compat.Data (unDataD)
+   Dec, ExpQ, conE, Con (..), TyVarBndr (..), nameBase,)
+import Language.Haskell.TH.Compat.Data (unDataD, unNewtypeD)
 import Data.List (foldl')
 
 import Data.Functor.ProductIsomorphic.Unsafe (ProductConstructor (..))
@@ -30,7 +31,12 @@
 recordInfo' :: Info -> Maybe (((TypeQ, [Name]), ExpQ), (Maybe [Name], [TypeQ]))
 recordInfo' =  d  where
   d (TyConI tcon) = do
-    (_cxt, tcn, bs, _mk, [r], _ds) <- unDataD tcon
+    (tcn, bs, r)  <-
+      do (_cxt, tcn, bs, _mk, [r], _ds)  <-  unDataD tcon
+         Just (tcn, bs, r)
+      <|>
+      do (_cxt, tcn, bs, _mk,  r , _ds)  <-  unNewtypeD tcon
+         Just (tcn, bs, r)
     let vns = map getTV bs
     case r of
       NormalC dcn ts   -> Just (((buildT tcn vns, vns), conE dcn), (Nothing, [return t | (_, t) <- ts]))
@@ -46,9 +52,19 @@
 reifyRecordType :: Name -> Q (((TypeQ, [Name]), ExpQ), (Maybe [Name], [TypeQ]))
 reifyRecordType recTypeName =
   maybe
-  (fail $ "Defined record type constructor not found: " ++ show recTypeName)
+  (fail msgOnErr)
   return
   . recordInfo' =<< reify recTypeName
+  where
+    recTypeNameS = show recTypeName
+    recTypeNameB = nameBase recTypeName
+    msgOnErr =
+      "Valid record type constructor not found: " ++ recTypeNameS ++ ".\n"
+      ++ "    Possible causes:\n"
+      ++ "      - " ++ recTypeNameB ++ " is not a type name.\n"
+      ++ "        (Type name must be prefixed with double-single-quotes: e.g. ''" ++ recTypeNameB ++ ")\n"
+      ++ "      - " ++ recTypeNameB ++ " has multiple data constructors.\n"
+      ++ "        (Currently, only types with exactly *one* data constructors are supported)\n"
 
 -- | Make template of ProductConstructor instance from type constructor name.
 defineProductConstructor :: Name     -- ^ name of product or record type constructor
diff --git a/test/doTH.hs b/test/doTH.hs
new file mode 100644
--- /dev/null
+++ b/test/doTH.hs
@@ -0,0 +1,35 @@
+{-# LANGUAGE TemplateHaskell #-}
+{-# LANGUAGE FlexibleInstances #-}
+
+import Language.Haskell.TH (runIO)
+
+import Data.Functor.ProductIsomorphic.TH
+  (reifyRecordType, defineProductConstructor)
+
+
+newtype NNormal = NNormal Int
+newtype NRec = NRec { _nrec :: Int }
+data DNormal = DNormal Int
+data DRec = DRec { _drec :: Int }
+
+-- expect compilation error on test failure
+$(mapM_ (\(tn, dn) -> do
+           runIO . putStrLn $ "testing " ++ show (tn, dn)
+           --- (((TypeQ, [Name]), ExpQ), (Maybe [Name], [TypeQ]))
+           (((tq, vns), eq), (fns, ftqs)) <- reifyRecordType tn
+           ty   <- tq
+           expr <- eq
+           fts  <- sequence ftqs
+           runIO $ print (((ty, vns), expr), (fns, fts))
+        )
+  [(''NNormal, 'NNormal), (''NRec, 'NRec),
+   (''DNormal, 'DNormal), (''DRec, 'DRec)]
+  >> return [])
+
+$(defineProductConstructor ''NNormal)
+$(defineProductConstructor ''NRec)
+$(defineProductConstructor ''DNormal)
+$(defineProductConstructor ''DRec)
+
+main :: IO ()
+main = return ()