diff --git a/workers/exporters/bundle.ini b/workers/exporters/bundle.ini
index 07735212d..d35e4ffac 100644
--- a/workers/exporters/bundle.ini
+++ b/workers/exporters/bundle.ini
@@ -46,6 +46,14 @@ value = get('uri')
 path = value
 value = get('versions').last().get(env('field.0'))
 
+[singleton]
+[singleton/validate]
+path = id
+rule = required|string
+
+path = value
+rule = required
+
 [TARDump]
 compress = true
 manifest = env('manifest')