diff --git a/build-constraints.yaml b/build-constraints.yaml
index 0c75114f..0cf6482a 100644
--- a/build-constraints.yaml
+++ b/build-constraints.yaml
@@ -3510,6 +3510,8 @@ packages:
         - servant-server < 0.12
         - servant-docs < 0.11.1
         - servant-foreign < 0.10.2
+        - slack-web < 0.2.0.2
+        - servant-client-core < 0.12
 
 # end of packages