diff --git a/build-constraints.yaml b/build-constraints.yaml
index 72d6c677..3b2f934b 100644
--- a/build-constraints.yaml
+++ b/build-constraints.yaml
@@ -1612,7 +1612,7 @@ packages:
         - bank-holidays-england
 
     "Haskell Servant <haskell-servant-maintainers@googlegroups.com>":
-        - servant
+        - servant < 0.18.3
         - servant-blaze
         - servant-cassava
         - servant-client