diff --git a/genvalidity-hspec.cabal b/genvalidity-hspec.cabal
--- a/genvalidity-hspec.cabal
+++ b/genvalidity-hspec.cabal
@@ -2,10 +2,10 @@
 --
 -- see: https://github.com/sol/hpack
 --
--- hash: 963ec860fbcd5ff6bc1148b8abc7c91d1bf7a7ef77e0ed0181ffc136b6e37005
+-- hash: 6fe4772b4a007d5e358a91f2500b29b0161e709fcfceb3e14c58240fffa9d8e7
 
 name:           genvalidity-hspec
-version:        0.6.1.0
+version:        0.6.1.1
 synopsis:       Standard spec's for GenValidity instances
 description:    Note: There are companion packages for this library:
                 .
@@ -42,6 +42,7 @@
     , genvalidity-property >=0.2
     , hspec
     , hspec-core
+    , transformers
     , validity >=0.5
   exposed-modules:
       Test.Validity
diff --git a/src/Test/Validity/Utils.hs b/src/Test/Validity/Utils.hs
--- a/src/Test/Validity/Utils.hs
+++ b/src/Test/Validity/Utils.hs
@@ -19,6 +19,9 @@
     , shouldBeInvalid
     ) where
 
+import Control.Monad.Trans.Writer (mapWriterT)
+import Control.Arrow (second)
+
 import Data.Data
 
 import Test.Hspec
@@ -58,12 +61,18 @@
 instance Functor Anon where
     fmap f (Anon a) = Anon (f a)
 
+-- I'm not sure why mapSpecTree was removed from hspec-core,
+-- but it has been copied here for convenience.
+-- https://github.com/hspec/hspec/commit/020c7ecc4a73c24af38e9fab049f60bb9aec6981#diff-29cb22f0ef6e98086a71fc045847bd21L22
+mapSpecTree' :: (SpecTree a -> SpecTree b) -> SpecM a r -> SpecM b r
+mapSpecTree' f (SpecM specs) = SpecM (mapWriterT (fmap (second (map f))) specs)
+
 -- | Asserts that a given 'Spec' tree fails _somewhere_.
 --
 -- It also shows the given string when reporting that the tree unexpectedly
 -- succeeded.
 failsBecause :: String -> SpecWith () -> SpecWith ()
-failsBecause s = mapSpecTree go
+failsBecause s = mapSpecTree' go
   where
     go :: SpecTree () -> SpecTree ()
     go sp =