diff --git a/pystarport/cluster.py b/pystarport/cluster.py
index c8c6aca..cfa6127 100644
--- a/pystarport/cluster.py
+++ b/pystarport/cluster.py
@@ -1096,7 +1096,7 @@ def format_value(v, ctx):
 if __name__ == "__main__":
     interact("rm -r data; mkdir data", ignore_error=True)
     data_dir = Path("data")
-    init_cluster(data_dir, "config.yaml", 26650)
+    init_cluster(data_dir, "config.yaml", 26650, None)
     supervisord = start_cluster(data_dir)
     t = start_tail_logs_thread(data_dir)
     supervisord.wait()
diff --git a/pystarport/expansion.py b/pystarport/expansion.py
index c9dade7..00d010b 100644
--- a/pystarport/expansion.py
+++ b/pystarport/expansion.py
@@ -81,10 +81,10 @@ def expand(dotenv):
     if dotenv is not None:
         if "dotenv" in config:
             _ = config.pop("dotenv", {})  # remove dotenv field if exists
-        dotenv = dotenv
-        config = expand(dotenv)
+        dotenv_path = dotenv
+        config = expand(dotenv_path)
     elif "dotenv" in config:
-        dotenv = config.pop("dotenv", {})  # pop dotenv field if exists
-        config = expand(dotenv)
+        dotenv_path = config.pop("dotenv", {})  # pop dotenv field if exists
+        config = expand(dotenv_path)
 
     return config