diff --git a/hazelcast/include/hazelcast/logger.h b/hazelcast/include/hazelcast/logger.h
index 75a2fb36d9..ffea4c8ea6 100644
--- a/hazelcast/include/hazelcast/logger.h
+++ b/hazelcast/include/hazelcast/logger.h
@@ -3,6 +3,7 @@
 #include <string>
 #include <functional>
 #include <limits>
+#include <mutex>
 
 #include "hazelcast/util/export.h"
 
@@ -52,6 +53,7 @@ class HAZELCAST_API logger {
     const std::string cluster_name_;
     const level level_;
     const handler_type handler_;
+    static std::mutex cout_lock_;
 };
 
 enum class logger::level : int {
diff --git a/hazelcast/src/hazelcast/logger.cpp b/hazelcast/src/hazelcast/logger.cpp
index 943ee687c9..7465743d53 100644
--- a/hazelcast/src/hazelcast/logger.cpp
+++ b/hazelcast/src/hazelcast/logger.cpp
@@ -1,6 +1,5 @@
 #include <iomanip>
 #include <iostream>
-#include <mutex>
 #include <sstream>
 #include <chrono>
 #include <ctime>
@@ -42,7 +41,7 @@ logger::logger(std::string instance_name, std::string cluster_name, level level,
     : instance_name_{ std::move(instance_name) }
     , cluster_name_{ std::move(cluster_name) }
     , level_{ level }
-    , handler_{ std::move(handler) } 
+    , handler_{ std::move(handler) }
 {}
 
 bool logger::enabled(level lvl) noexcept {
@@ -69,10 +68,14 @@ std::tm time_t_to_localtime(const std::time_t &t) {
 
 }
 
-void logger::default_handler(const std::string &instance_name,
-                             const std::string &cluster_name,
-                             level lvl, 
-                             const std::string &msg) noexcept {
+std::mutex logger::cout_lock_;
+
+void
+logger::default_handler(const std::string& instance_name,
+                        const std::string& cluster_name,
+                        level lvl,
+                        const std::string& msg) noexcept
+{
 
     auto tp = std::chrono::system_clock::now();
     auto t = std::chrono::system_clock::to_time_t(tp);
@@ -80,7 +83,7 @@ void logger::default_handler(const std::string &instance_name,
 
     auto dur = tp.time_since_epoch();
     auto sec = std::chrono::duration_cast<std::chrono::seconds>(dur);
-    
+
     auto ms = std::chrono::duration_cast<std::chrono::milliseconds>(dur - sec).count();
 
     std::ostringstream sstrm;
@@ -96,11 +99,10 @@ void logger::default_handler(const std::string &instance_name,
           << '\n';
 
     {
-        static std::mutex cout_lock;
-        std::lock_guard<std::mutex> g(cout_lock);
+        std::lock_guard<std::mutex> g(cout_lock_);
         std::cout << sstrm.str() << std::flush;
     }
-} 
+}
 
 
 } // namespace hazelcast