diff --git a/build-constraints.yaml b/build-constraints.yaml
index 3a85b21f..3ed4d980 100644
--- a/build-constraints.yaml
+++ b/build-constraints.yaml
@@ -3279,6 +3279,7 @@ packages:
 
         # https://github.com/fpco/stackage/issues/2595
         - cassava < 0.5.0.0
+        - cassava-conduit < 0.4.0.0 # because of above and #2586
 
         # https://github.com/centromere/pipes-cacophony/issues/4
         - cacophony < 0.10.0 # causes failure in pipes-cacophony