diff --git a/pika-build-config/lto.sh b/pika-build-config/lto.sh
index 3fdafe71d..ad4dac95e 100644
--- a/pika-build-config/lto.sh
+++ b/pika-build-config/lto.sh
@@ -1,5 +1,5 @@
-export PIKA_PACKAGE_VERSION="4:6.1.3-1"
-export PIKA_PACKAGE_NAME="kdeplasma-addons"
+export PIKA_PACKAGE_VERSION="3.9.15-1"
+export PIKA_PACKAGE_NAME="python-orjson"
 export PIKA_PACKAGE_PATCH=false
 export PIKA_REBUILD=false
 export PIKA_REBUILD_VERSION="b0"