diff --git a/llama_stack/cli/stack/_build.py b/llama_stack/cli/stack/_build.py
index 8909486b3..f6f72946a 100644
--- a/llama_stack/cli/stack/_build.py
+++ b/llama_stack/cli/stack/_build.py
@@ -266,8 +266,8 @@ def run_stack_build_command(args: argparse.Namespace) -> None:
     if args.run:
         config_dict = yaml.safe_load(run_config.read_text())
         config = parse_and_maybe_upgrade_config(config_dict)
-        if not os.path.exists(config.external_providers_dir):
-            os.makedirs(config.external_providers_dir, exist_ok=True)
+        if config.external_providers_dir and not config.external_providers_dir.exists():
+            config.external_providers_dir.mkdir(exist_ok=True)
         run_args = formulate_run_args(args.image_type, args.image_name, config, args.template)
         run_args.extend([str(os.getenv("LLAMA_STACK_PORT", 8321)), "--config", run_config])
         run_command(run_args)