diff --git a/witch.cabal b/witch.cabal
index db5de89..f608961 100644
--- a/witch.cabal
+++ b/witch.cabal
@@ -81,7 +81,7 @@ test-suite witch-test-suite
 
   build-depends:
     , HUnit >= 1.6.1 && < 1.7
-    , transformers >= 0.5.2 && < 0.7
+    , transformers >= 0.5.6 && < 0.7
   hs-source-dirs: source/test-suite
   main-is: Main.hs
   type: exitcode-stdio-1.0