diff --git a/build-constraints.yaml b/build-constraints.yaml
index 94616705..de52b789 100644
--- a/build-constraints.yaml
+++ b/build-constraints.yaml
@@ -3986,7 +3986,7 @@ packages:
         - eap
         - failable
         - ttl-hashtables < 0 # hashable-1.3.0
-        - radius
+        - radius < 0 # MonadFail
         - structured-cli < 0 # MonadFail
 
     "Jan Path <jan@jpath.de> @janpath":