diff --git a/build-constraints.yaml b/build-constraints.yaml
index b7b65fcd..0842aee9 100644
--- a/build-constraints.yaml
+++ b/build-constraints.yaml
@@ -4396,8 +4396,8 @@ packages:
         - alg
         - category
         - constraint
-        - dual
-        - either-both
+        - dual < 0 # deprecated (https://hackage.haskell.org/package/dual) and not ghc 9.6 ready
+        - either-both < 0 # deprecated (https://hackage.haskell.org/package/either-both) and not ghc 9.6 ready
         - filtrable
         - foldable1
         - hs-functors