diff --git a/endpoints/index.py b/endpoints/index.py
index e4a8fdf73..0004ef8c1 100644
--- a/endpoints/index.py
+++ b/endpoints/index.py
@@ -180,7 +180,11 @@ def get_repository_images(namespace, repository):
     resp = make_response(json.dumps(all_images), 200)
     resp.mimetype = 'application/json'
 
-    mixpanel.track(get_authenticated_user().username, 'pull_repo')
+    pull_username = 'anonymous'
+    if get_authenticated_user():
+      pull_username = get_authenticated_user().username
+
+    mixpanel.track(pull_username, 'pull_repo')
 
     return resp