diff --git a/pika-build-config/lto.sh b/pika-build-config/lto.sh
index 6cb092b1a..594071071 100644
--- a/pika-build-config/lto.sh
+++ b/pika-build-config/lto.sh
@@ -1,5 +1,5 @@
-export PIKA_PACKAGE_VERSION="2.9.2-2"
-export PIKA_PACKAGE_NAME="pydantic"
+export PIKA_PACKAGE_VERSION="1.1.17-3"
+export PIKA_PACKAGE_NAME="libclass-date-perl"
 export PIKA_PACKAGE_PATCH=false
 export PIKA_REBUILD=false
 export PIKA_REBUILD_VERSION="b0"