diff --git a/pika-build-config/lto.sh b/pika-build-config/lto.sh
index ecba5bf1a..ad4dac95e 100644
--- a/pika-build-config/lto.sh
+++ b/pika-build-config/lto.sh
@@ -1,5 +1,5 @@
-export PIKA_PACKAGE_VERSION="1:20~++20240726085032+92a06546ab50-1~exp1"
-export PIKA_PACKAGE_NAME="llvm-toolchain-snapshot"
+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"