diff --git a/kumonoboru-prune.timer b/kumonoboru-prune.timer
new file mode 100644
index 0000000..f02c1e1
--- /dev/null
+++ b/kumonoboru-prune.timer
@@ -0,0 +1,9 @@
+[Unit]
+Description=Kumonoboru - Cloud backup utility
+
+[Timer]
+OnCalendar=monthly
+Persistent=true
+
+[Install]
+WantedBy=timers.target