diff --git a/configs/pipeline_registry.json b/configs/pipeline_registry.json
index 856f305..46e7433 100644
--- a/configs/pipeline_registry.json
+++ b/configs/pipeline_registry.json
@@ -2,7 +2,7 @@
     "pipelines": {
         "xiaozhan": {
             "enabled": true,
-            "config_file": "configs/pipelines/xiaozhan.yml",
+            "config_file": "configs/pipelines/xiaozhan.yaml",
             "graph_id": "routing",
             "overrides": {
                 "llm_name": "qwen-plus"
@@ -10,7 +10,7 @@
         },
         "blueberry": {
             "enabled": true,
-            "config_file": "configs/pipelines/blueberry.yml",
+            "config_file": "configs/pipelines/blueberry.yaml",
             "graph_id": "react",
             "overrides": {
                 "llm_name": "qwen-plus"
diff --git a/lang_agent/eval/evaluator.py b/lang_agent/eval/evaluator.py
index b31f9c7..8af9c9a 100644
--- a/lang_agent/eval/evaluator.py
+++ b/lang_agent/eval/evaluator.py
@@ -96,7 +96,7 @@ class Evaluator:
         
         df_m.to_csv(metric_f)
 
-        self.config.save_config(f"{head_path}-{n_exp}.yml")
+        self.config.save_config(f"{head_path}-{n_exp}.yaml")
     
     def format_result_df(self, df:pd.DataFrame):
 
diff --git a/lang_agent/fastapi_server/front_apis.py b/lang_agent/fastapi_server/front_apis.py
index 11197dd..5dfffac 100644
--- a/lang_agent/fastapi_server/front_apis.py
+++ b/lang_agent/fastapi_server/front_apis.py
@@ -511,7 +511,7 @@ async def create_pipeline(body: PipelineCreateRequest):
             ),
         )
 
-    config_file = f"configs/pipelines/{pipeline_id}.yml"
+    config_file = f"configs/pipelines/{pipeline_id}.yaml"
     config_abs_dir = osp.join(_PROJECT_ROOT, "configs", "pipelines")
     try:
         build_fn(
diff --git a/lang_agent/front_api/build_server_utils.py b/lang_agent/front_api/build_server_utils.py
index 991894e..6e83a0c 100644
--- a/lang_agent/front_api/build_server_utils.py
+++ b/lang_agent/front_api/build_server_utils.py
@@ -22,7 +22,7 @@ def opt_to_config(save_path: str, *nargs):
 def _build_and_load_pipeline_config(
     pipeline_id: str, pipeline_config_dir: str, cmd: List[str]
 ):
-    save_config_f = osp.join(pipeline_config_dir, f"{pipeline_id}.yml")
+    save_config_f = osp.join(pipeline_config_dir, f"{pipeline_id}.yaml")
     opt_to_config(save_config_f, *cmd)
 
     # TODO: think if returning the built pipeline is better or just the config obj for front_api