diff --git a/app/utils/uploader.py b/app/utils/uploader.py
index bea7d17..51bed60 100644
--- a/app/utils/uploader.py
+++ b/app/utils/uploader.py
@@ -44,7 +44,7 @@ class DiskChunkUploadBackend(ChunkUploadBackend):
             return
         self._file.close()
         relative_path = settings.MEDIA_DIR.relative_to(settings.BASE_DIR)
-        return os.path.join(relative_path, self._file.name)
+        return str(relative_path / self._file.name)
 
     def abort(self):
         if self._file: