diff --git a/src/metriki/app.py b/src/metriki/app.py
index b8e930f..3ed01fe 100644
--- a/src/metriki/app.py
+++ b/src/metriki/app.py
@@ -27,7 +27,7 @@ class BaseView(web.View):
             ip=self.ip,
             key=key,
             value=json.dumps(value,default=str),
-            created=datetime.now()
+            created=str(datetime.now())
         )
         record.update(kwargs)
         self.db['session'].upsert(dict(