diff --git a/build-constraints.yaml b/build-constraints.yaml
index 7dbc7e97..28e599fa 100644
--- a/build-constraints.yaml
+++ b/build-constraints.yaml
@@ -3741,6 +3741,9 @@ packages:
         # https://github.com/commercialhaskell/stackage/issues/3972
         - vector-algorithms < 0.8.0.0
 
+        # https://github.com/commercialhaskell/stackage/issues/3984
+        - unbound-generics < 0.4
+
 # end of packages
 
 # Package flags are applied to individual packages, and override the values of