diff --git a/src/common/model/tvl.h b/src/common/model/tvl.h
index a7585c28..b77dcf7e 100644
--- a/src/common/model/tvl.h
+++ b/src/common/model/tvl.h
@@ -71,4 +71,4 @@ inline value_t any_of(InputIterator first, InputIterator last, Predicate pred)
 
     return res;
 }
-} // namespace clanguml::common::model::tvl;
\ No newline at end of file
+} // namespace clanguml::common::model::tvl
\ No newline at end of file
diff --git a/src/config/config.cc b/src/config/config.cc
index 92af61ff..6890ecf3 100644
--- a/src/config/config.cc
+++ b/src/config/config.cc
@@ -21,8 +21,7 @@
 
 #include <filesystem>
 
-namespace clanguml {
-namespace config {
+namespace clanguml::config {
 
 config load(const std::string &config_file)
 {
@@ -218,8 +217,7 @@ template <> void append_value<plantuml>(plantuml &l, const plantuml &r)
 {
     l.append(r);
 }
-} // namespace config
-} // namespace clanguml
+} // namespace clanguml::config
 
 namespace YAML {
 using clanguml::common::model::access_t;
diff --git a/src/decorators/decorators.cc b/src/decorators/decorators.cc
index 4bebf67f..90ed3a58 100644
--- a/src/decorators/decorators.cc
+++ b/src/decorators/decorators.cc
@@ -22,8 +22,7 @@
 #include <string>
 #include <string_view>
 
-namespace clanguml {
-namespace decorators {
+namespace clanguml::decorators {
 
 std::shared_ptr<decorator> decorator::from_string(std::string_view c)
 {
@@ -208,5 +207,4 @@ std::vector<std::shared_ptr<decorator>> parse(
     return res;
 };
 
-} // namespace decorators
-} // namespace clanguml
+} // namespace clanguml::decorators