diff --git a/pika-build-config/lto.sh b/pika-build-config/lto.sh
index d25c1bd9d..8c3208752 100644
--- a/pika-build-config/lto.sh
+++ b/pika-build-config/lto.sh
@@ -1,5 +1,5 @@
-export PIKA_PACKAGE_VERSION="2.0.1-1"
-export PIKA_PACKAGE_NAME="pyrfc3339"
+export PIKA_PACKAGE_VERSION="6.12.0.199+dfsg-2.1"
+export PIKA_PACKAGE_NAME="mono"
 export PIKA_PACKAGE_PATCH=false
 export PIKA_REBUILD=false
 export PIKA_REBUILD_VERSION="b0"