diff --git a/tools/ndncert-ca-status.cpp b/tools/ndncert-ca-status.cpp
index 2d0c0f9..c4f14c1 100644
--- a/tools/ndncert-ca-status.cpp
+++ b/tools/ndncert-ca-status.cpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /*
- * Copyright (c) 2017-2021, Regents of the University of California.
+ * Copyright (c) 2017-2022, Regents of the University of California.
  *
  * This file is part of ndncert, a certificate management system based on NDN.
  *
@@ -27,8 +27,7 @@
 
 #include <iostream>
 
-namespace ndncert {
-namespace ca {
+namespace ndncert::ca {
 
 static int
 main(int argc, char* argv[])
@@ -74,8 +73,7 @@
   return 0;
 }
 
-} // namespace ca
-} // namespace ndncert
+} // namespace ndncert::ca
 
 int
 main(int argc, char* argv[])