diff --git a/build-constraints.yaml b/build-constraints.yaml
index ce2864e9..f93cdc66 100644
--- a/build-constraints.yaml
+++ b/build-constraints.yaml
@@ -452,7 +452,7 @@ packages:
     "Michael Snoyman michael@snoyman.com @snoyberg":
         - bzlib-conduit
         - mega-sdist
-        - case-insensitive
+        - case-insensitive < 1.2.1
         - classy-prelude-yesod
         - conduit-combinators
         - conduit-extra