Index: b/haddock-library.cabal
===================================================================
--- a/haddock-library.cabal
+++ b/haddock-library.cabal
@@ -76,7 +76,7 @@ test-suite spec
       base-compat   ^>= 0.9.3
     , containers   >= 0.4.2.1 && < 0.6
     , transformers   >= 0.3.0   && < 0.6
-    , hspec         ^>= 2.4.4
+    , hspec         >= 2.4.4 && < 2.6
     , QuickCheck    ^>= 2.11
 
   build-depends: attoparsec
