diff --git a/build-constraints.yaml b/build-constraints.yaml
index 7dfb7942..ac7a0021 100644
--- a/build-constraints.yaml
+++ b/build-constraints.yaml
@@ -5219,7 +5219,7 @@ expected-test-failures:
     - heap
 
     # https://github.com/commercialhaskell/stackage/issues/4289
-    # Diff
+    - Diff
 
     # https://github.com/commercialhaskell/stackage/issues/4294
     - asif