diff --git a/bioflow_service/app/services/bioflow/extensions.py b/bioflow_service/app/services/bioflow/extensions.py
index 5a00658..0e3c143 100644
--- a/bioflow_service/app/services/bioflow/extensions.py
+++ b/bioflow_service/app/services/bioflow/extensions.py
@@ -420,8 +420,9 @@ class ExtensionStore:
             dest.parent.mkdir(parents=True, exist_ok=True)
             dest.write_bytes(blob)
             saved_code.append(str(dest.relative_to(ext_dir)))
-            mirror = converted_code / dest.name
-            mirror.write_bytes(blob)  # converted_code 初始 = raw_code 拷贝（175 同款）
+            mirror = converted_code / dest.relative_to(raw_code)
+            mirror.parent.mkdir(parents=True, exist_ok=True)
+            mirror.write_bytes(blob)  # converted_code 初始 = raw_code 拷贝（175 同款；2026-09-15 修复:保留嵌套结构）
         saved_data: list[str] = []
         for rel, blob in data_files or []:
             dest = raw_test_data / safe_filename(rel)