cache repo per storage object
diff --git a/reclass/storage/yaml_git/__init__.py b/reclass/storage/yaml_git/__init__.py
index 782c274..9274148 100644
--- a/reclass/storage/yaml_git/__init__.py
+++ b/reclass/storage/yaml_git/__init__.py
@@ -192,10 +192,9 @@
 
 class ExternalNodeStorage(NodeStorageBase):
 
-    _repos = dict()
-
     def __init__(self, nodes_uri, classes_uri):
         super(ExternalNodeStorage, self).__init__(STORAGE_NAME)
+        self._repos = dict()
 
         if nodes_uri is not None:
             self._nodes_uri = GitURI({ 'branch': 'master' })