diff --git a/pika-build-config/lto.sh b/pika-build-config/lto.sh
index 040a84a9e..e1b78753f 100644
--- a/pika-build-config/lto.sh
+++ b/pika-build-config/lto.sh
@@ -1,5 +1,5 @@
-export PIKA_PACKAGE_VERSION="3.4.0-1"
-export PIKA_PACKAGE_NAME="libzdb"
+export PIKA_PACKAGE_VERSION="5.1-502+ds-1"
+export PIKA_PACKAGE_NAME="ocaml-merlin"
 export PIKA_PACKAGE_PATCH=false
 export PIKA_REBUILD=false
 export PIKA_REBUILD_VERSION="b0"