diff --git a/utils/Worker.cpp b/utils/Worker.cpp
index d2b60c8..e1c7aee 100644
--- a/utils/Worker.cpp
+++ b/utils/Worker.cpp
@@ -30,7 +30,7 @@
 }
 
 int Worker::InitWorker() {
-  std::lock_guard<std::mutex> lk(mutex_);
+  const std::lock_guard<std::mutex> lk(mutex_);
   if (initialized())
     return -EALREADY;