diff --git a/build-constraints.yaml b/build-constraints.yaml
index 0e3012a1..7e8bad7a 100644
--- a/build-constraints.yaml
+++ b/build-constraints.yaml
@@ -609,7 +609,7 @@ packages:
         - ap-normalize
         - boltzmann-samplers
         - first-class-families
-        - generic-data
+        - generic-data < 0  # https://github.com/commercialhaskell/stackage/issues/6531
         - generic-data-surgery
         - generic-functor
         - generic-random
@@ -2299,7 +2299,7 @@ packages:
         - lens-typelevel
         - list-witnesses
         - nonempty-containers
-        - one-liner-instances
+        - one-liner-instances < 0  # https://github.com/commercialhaskell/stackage/issues/6531
         - prompt
         - servant-cli
         - tagged-binary