diff --git a/wally/test_run_class.py b/wally/test_run_class.py
index a0c014f..fea846d 100644
--- a/wally/test_run_class.py
+++ b/wally/test_run_class.py
@@ -43,7 +43,7 @@
 
     def merge_node(self, creds: ConnCreds, roles: Set[str]) -> NodeInfo:
         info = NodeInfo(creds, roles)
-        nid = info.node_id()
+        nid = info.node_id
 
         if nid in self.nodes_info:
             self.nodes_info[nid].roles.update(info.roles)