diff --git a/src/cli/cli_handler.cc b/src/cli/cli_handler.cc
index 18820674..44a4c4f2 100644
--- a/src/cli/cli_handler.cc
+++ b/src/cli/cli_handler.cc
@@ -56,7 +56,7 @@ void cli_handler::setup_logging()
     }
 }
 
-cli_flow_t cli_handler::parse(int argc, const char *argv[])
+cli_flow_t cli_handler::parse(int argc, const char **argv)
 {
     app.add_option("-c,--config", config_path,
         "Location of configuration file, when '-' read from stdin");
@@ -104,7 +104,7 @@ cli_flow_t cli_handler::parse(int argc, const char *argv[])
         return cli_flow_t::kExit;
     }
     catch (const CLI::ParseError &e) {
-        exit(app.exit(e));
+        exit(app.exit(e)); // NOLINT(concurrency-mt-unsafe)
     }
 
     if (quiet || dump_config)
@@ -115,7 +115,7 @@ cli_flow_t cli_handler::parse(int argc, const char *argv[])
     return cli_flow_t::kContinue;
 }
 
-cli_flow_t cli_handler::handle_options(int argc, const char *argv[])
+cli_flow_t cli_handler::handle_options(int argc, const char **argv)
 {
     auto res = parse(argc, argv);
 
@@ -558,4 +558,4 @@ cli_flow_t cli_handler::print_config()
 
     return cli_flow_t::kExit;
 }
-} // namespace clanguml::options
\ No newline at end of file
+} // namespace clanguml::cli
\ No newline at end of file
diff --git a/src/cli/cli_handler.h b/src/cli/cli_handler.h
index 11633087..7c917c77 100644
--- a/src/cli/cli_handler.h
+++ b/src/cli/cli_handler.h
@@ -41,7 +41,7 @@ public:
      * @param argv
      * @return
      */
-    cli_flow_t handle_options(int argc, const char *argv[]);
+    cli_flow_t handle_options(int argc, const char **argv);
 
     /**
      * Print the program version and basic information
@@ -135,7 +135,7 @@ public:
     clanguml::config::config config;
 
 private:
-    cli_flow_t parse(int argc, const char *argv[]);
+    cli_flow_t parse(int argc, const char **argv);
 
     cli_flow_t handle_pre_config_options();
 
@@ -149,5 +149,4 @@ private:
     std::shared_ptr<spdlog::logger> logger_;
     CLI::App app{"Clang-based UML diagram generator for C++"};
 };
-
-} // namespace clanguml::options
\ No newline at end of file
+} // namespace clanguml::cli
\ No newline at end of file
diff --git a/src/common/model/enums.cc b/src/common/model/enums.cc
index 7d199d62..3dfab613 100644
--- a/src/common/model/enums.cc
+++ b/src/common/model/enums.cc
@@ -140,14 +140,14 @@ diagram_t from_string(const std::string &s)
 {
     if (s == "class")
         return diagram_t::kClass;
-    else if (s == "sequence")
+    if (s == "sequence")
         return diagram_t::kSequence;
-    else if (s == "include")
+    if (s == "include")
         return diagram_t::kInclude;
-    else if (s == "package")
+    if (s == "package")
         return diagram_t::kPackage;
-    else
-        throw std::runtime_error{"Invalid diagram type: " + s};
+
+    throw std::runtime_error{"Invalid diagram type: " + s};
 }
 
 } // namespace clanguml::common::model
diff --git a/src/config/config.h b/src/config/config.h
index f3a147bd..c13ffc08 100644
--- a/src/config/config.h
+++ b/src/config/config.h
@@ -52,7 +52,7 @@ struct plantuml {
 
 struct diagram_template {
     std::string description;
-    common::model::diagram_t type;
+    common::model::diagram_t type{common::model::diagram_t::kClass};
     std::string jinja_template;
 };