diff --git a/build-constraints.yaml b/build-constraints.yaml
index 400a2f58..d52a24c5 100644
--- a/build-constraints.yaml
+++ b/build-constraints.yaml
@@ -3737,7 +3737,7 @@ packages:
         - harpie
         - harpie-numhask
         - markup-parse
-        - mealy
+        - mealy < 0.5.1.0 || > 0.5.1.0 # compilation fails for this version
         - numhask
         - numhask-space
         - perf