diff --git a/build-constraints.yaml b/build-constraints.yaml
index a78c7e94..a6495a82 100644
--- a/build-constraints.yaml
+++ b/build-constraints.yaml
@@ -2183,7 +2183,7 @@ packages:
         - configurator-export
         - decidable
         - emd < 0 # via typelits-witnesses
-        - functor-products
+        - functor-products < 0 # https://github.com/mstksg/functor-products/issues/1
         - hamilton < 0 # via vty
         - hmatrix-backprop
         - hmatrix-vector-sized