diff --git a/build-constraints.yaml b/build-constraints.yaml
index bc5ea9d3..9907bce6 100644
--- a/build-constraints.yaml
+++ b/build-constraints.yaml
@@ -771,6 +771,7 @@ packages:
         - th-orphans < 0.9
         - file-location < 0.4.7
         - th-desugar < 1.5.1
+        - singletons < 1.1.1
 
         # https://github.com/fpco/stackage/issues/442
         - blaze-builder < 0.4