diff --git a/build-constraints.yaml b/build-constraints.yaml
index e7553487..7e91fbc4 100644
--- a/build-constraints.yaml
+++ b/build-constraints.yaml
@@ -1711,6 +1711,9 @@ packages:
         # https://github.com/fpco/stackage/issues/968
         - bifunctors < 5.1
 
+        # https://github.com/fpco/stackage/issues/973
+        - constraints < 0.6
+
 # end of packages