diff --git a/daemon/table/name-tree-hashtable.cpp b/daemon/table/name-tree-hashtable.cpp
index fc17523..390507d 100644
--- a/daemon/table/name-tree-hashtable.cpp
+++ b/daemon/table/name-tree-hashtable.cpp
@@ -27,8 +27,7 @@
 #include "common/city-hash.hpp"
 #include "common/logger.hpp"
 
-namespace nfd {
-namespace name_tree {
+namespace nfd::name_tree {
 
 NFD_LOG_INIT(NameTreeHashtable);
 
@@ -278,5 +277,4 @@
   this->computeThresholds();
 }
 
-} // namespace name_tree
-} // namespace nfd
+} // namespace nfd::name_tree