diff --git a/src/api/project_routes.py b/src/api/project_routes.py
index 0f38255..fb9578b 100644
--- a/src/api/project_routes.py
+++ b/src/api/project_routes.py
@@ -8,15 +8,13 @@ from typing import Any, Dict, List, Optional
 from fastapi import APIRouter, HTTPException
 
 from src.blackboard.registry import ProjectRegistry
+from src.utils import get_data_root
 
 router = APIRouter(prefix="/api/projects", tags=["projects"])
 
 
 def _registry() -> ProjectRegistry:
-    import os
-    root = Path(os.environ.get("BLACKBOARD_ROOT",
-        str(Path.home() / ".sanguo_projects" / "sanguo_moziplus_v2" / "projects")))
-    return ProjectRegistry(root)
+    return ProjectRegistry(get_data_root())
 
 
 @router.get("")