diff --git a/src/commands/report/node_report.cc b/src/commands/report/node_report.cc
index 4465287..66ae725 100644
--- a/src/commands/report/node_report.cc
+++ b/src/commands/report/node_report.cc
@@ -27,7 +27,7 @@ static void WriteNodeReport(JSONWriter *writer, string location, string message,
   writer->json_keyvalue("pid", GetPid());
   writer->json_keyvalue("location", location);
   writer->json_keyvalue("message", message);
-  writer->json_keyvalue("nodeVersion", GetGlobalNodeVersion());
+  writer->json_keyvalue("nodeVersion", NODE_VERSION);
   writer->json_keyvalue("osVersion", GetOsVersion());
   writer->json_keyvalue("loadTime", GetStartTime("%Y-%m-%d %H:%M:%S"));
   writer->json_keyvalue("dumpTime", ConvertTime("%Y-%m-%d %H:%M:%S"));
@@ -54,4 +54,4 @@ void NodeReport::GetNodeReport(string filepath, string location, string message,
   WriteNodeReport(&writer, location, message, fatal_error);
   outfile.close();
 }
-}  // namespace xprofiler
\ No newline at end of file
+}  // namespace xprofiler
diff --git a/src/configure.h b/src/configure.h
index d623432..9e8d43a 100644
--- a/src/configure.h
+++ b/src/configure.h
@@ -3,6 +3,7 @@
 
 #include "library/common.h"
 #include "library/error.h"
+#include "logger.h"
 #include "nan.h"
 
 namespace xprofiler {
diff --git a/src/library/common.cc b/src/library/common.cc
index 9e0b781..131296e 100644
--- a/src/library/common.cc
+++ b/src/library/common.cc
@@ -17,23 +17,23 @@ using v8::Object;
 using v8::String;
 using v8::Value;
 
-static time_t load_time;
-static string global_node_version_string = NODE_VERSION;
+namespace per_process {
+time_t load_time;
+}
 
-void InitGlobalVariables() { time(&load_time); }
+void InitOnceLoadTime() { time(&per_process::load_time); }
 
 unsigned long GetUptime() {
   time_t current_time;
   time(&current_time);
-  return static_cast<unsigned long>(difftime(current_time, load_time));
+  return static_cast<unsigned long>(
+      difftime(current_time, per_process::load_time));
 }
 
 string GetStartTime(string format) {
   char time_string_day[32];
-  struct tm *ptm = localtime(&load_time);
+  struct tm *ptm = localtime(&per_process::load_time);
   strftime(time_string_day, sizeof(time_string_day), format.c_str(), ptm);
   return (string)time_string_day;
 }
-
-string GetGlobalNodeVersion() { return global_node_version_string; }
 }  // namespace xprofiler
diff --git a/src/library/common.h b/src/library/common.h
index 23c3a99..662ee8f 100644
--- a/src/library/common.h
+++ b/src/library/common.h
@@ -1,29 +1,20 @@
-#ifndef _SRC_LIBRARY_COMMON_H
-#define _SRC_LIBRARY_COMMON_H
+#ifndef XPROFILER_SRC_LIBRARY_COMMON_H
+#define XPROFILER_SRC_LIBRARY_COMMON_H
 
 #include "json.hpp"
 
 namespace xprofiler {
-using nlohmann::json;
-using std::function;
-using std::string;
-
-// xprofiler logger
-enum LOG_LEVEL { LOG_INFO, LOG_ERROR, LOG_DEBUG };
-enum LOG_TYPE { LOG_TO_FILE, LOG_TO_TTL };
-
-// global variables
-void InitGlobalVariables();
-string GetGlobalNodeVersion();
+void InitOnceLoadTime();
 
 // uptime
 unsigned long GetUptime();
-string GetStartTime(string format);
+std::string GetStartTime(std::string format);
 
 // commands
-#define COMMAND_CALLBACK(cb)                                 \
-  void cb(json command, string (*format)(const char *, ...), \
-          function<void(json)> success, function<void(string)> error)
+#define COMMAND_CALLBACK(cb)                                                \
+  void cb(nlohmann::json command, std::string (*format)(const char *, ...), \
+          std::function<void(nlohmann::json)> success,                      \
+          std::function<void(std::string)> error)
 }  // namespace xprofiler
 
-#endif
\ No newline at end of file
+#endif /* XPROFILER_SRC_LIBRARY_COMMON_H */
diff --git a/src/logger.cc b/src/logger.cc
index 68e1232..c600a0b 100644
--- a/src/logger.cc
+++ b/src/logger.cc
@@ -10,6 +10,7 @@
 
 #include "configure-inl.h"
 #include "platform/platform.h"
+#include "util.h"
 
 namespace xprofiler {
 using Nan::New;
@@ -21,17 +22,10 @@ using std::to_string;
 using v8::Local;
 using v8::String;
 
-#define WRITET_TO_FILE(type)                   \
-  uv_mutex_lock(&logger_mutex);                \
-  type##_stream.open(filepath, std::ios::app); \
-  type##_stream << log;                        \
-  type##_stream.close();                       \
-  uv_mutex_unlock(&logger_mutex);
-
-#define LOG_WITH_LEVEL(level)                     \
-  va_list args;                                   \
-  va_start(args, format);                         \
-  Log(LOG_LEVEL::level, log_type, format, &args); \
+#define LOG_WITH_LEVEL(level)                    \
+  va_list args;                                  \
+  va_start(args, format);                        \
+  Log(LOG_LEVEL::level, log_type, format, args); \
   va_end(args);
 
 #define JS_LOG_WITH_LEVEL(level)                                               \
@@ -49,12 +43,9 @@ using v8::String;
 static const int kMaxMessageLength = 2048;
 static const int kMaxFormatLength = 2048;
 
-static uv_mutex_t logger_mutex;
-
-// output
-static std::ofstream info_stream;
-static std::ofstream error_stream;
-static std::ofstream debug_stream;
+namespace per_process {
+uv_mutex_t logger_mutex;
+}
 
 static void WriteToFile(const LOG_LEVEL output_level, char *log) {
   // get time of date
@@ -74,19 +65,23 @@ static void WriteToFile(const LOG_LEVEL output_level, char *log) {
   switch (output_level) {
     case LOG_LEVEL::LOG_INFO:
       filepath += file_prefix + time_string_day + ".log";
-      WRITET_TO_FILE(info)
       break;
     case LOG_LEVEL::LOG_ERROR:
       filepath += file_prefix + "error-" + time_string_day + ".log";
-      WRITET_TO_FILE(error)
       break;
     case LOG_LEVEL::LOG_DEBUG:
       filepath += file_prefix + "debug-" + time_string_day + ".log";
-      WRITET_TO_FILE(debug)
       break;
     default:
-      break;
+      UNREACHABLE();
+  }
+
+  uv_mutex_lock(&per_process::logger_mutex);
+  {
+    std::ofstream ostream(filepath, std::ios::app);
+    ostream << log;
   }
+  uv_mutex_unlock(&per_process::logger_mutex);
 }
 
 static void Log(const LOG_LEVEL output_level, const char *type,
@@ -167,9 +162,8 @@ static void Log(const LOG_LEVEL output_level, const char *type,
   }
 }
 
-int InitLogger() {
-  int rc = uv_mutex_init(&logger_mutex);
-  return rc;
+void InitOnceLogger() {
+  CHECK_EQ(uv_mutex_init(&per_process::logger_mutex), 0);
 }
 
 /* native logger */
diff --git a/src/logger.h b/src/logger.h
index 6a5e10a..d07c866 100644
--- a/src/logger.h
+++ b/src/logger.h
@@ -1,5 +1,5 @@
-#ifndef SRC_LOGGER_H
-#define SRC_LOGGER_H
+#ifndef XPROFILER_SRC_LOGGER_H
+#define XPROFILER_SRC_LOGGER_H
 
 #include "library/common.h"
 #include "nan.h"
@@ -8,7 +8,11 @@ namespace xprofiler {
 using Nan::FunctionCallbackInfo;
 using v8::Value;
 
-int InitLogger();
+// xprofiler logger
+enum LOG_LEVEL { LOG_INFO, LOG_ERROR, LOG_DEBUG };
+enum LOG_TYPE { LOG_TO_FILE, LOG_TO_TTL };
+
+void InitOnceLogger();
 
 // normal external
 void Info(const char *log_type, const char *format, ...);
@@ -21,4 +25,4 @@ void JsError(const FunctionCallbackInfo<Value> &info);
 void JsDebug(const FunctionCallbackInfo<Value> &info);
 }  // namespace xprofiler
 
-#endif
\ No newline at end of file
+#endif /* XPROFILER_SRC_LOGGER_H */
diff --git a/src/util.h b/src/util.h
index 3436107..8b88320 100644
--- a/src/util.h
+++ b/src/util.h
@@ -24,9 +24,15 @@ struct AssertionInfo {
     xprofiler::Assert(args);                                                  \
   } while (0)
 
+#ifdef __GNUC__
 #define LIKELY(expr) __builtin_expect(!!(expr), 1)
 #define UNLIKELY(expr) __builtin_expect(!!(expr), 0)
 #define PRETTY_FUNCTION_NAME __PRETTY_FUNCTION__
+#else
+#define LIKELY(expr) expr
+#define UNLIKELY(expr) expr
+#define PRETTY_FUNCTION_NAME ""
+#endif
 
 #define STRINGIFY_(x) #x
 #define STRINGIFY(x) STRINGIFY_(x)
@@ -72,6 +78,9 @@ struct AssertionInfo {
 #define DCHECK_IMPLIES(a, b)
 #endif
 
+#define UNREACHABLE(...) \
+  ERROR_AND_ABORT("Unreachable code reached" __VA_OPT__(": ") __VA_ARGS__)
+
 // Convenience wrapper around v8::String::NewFromOneByte
 inline v8::Local<v8::String> OneByteString(v8::Isolate* isolate,
                                            const char* data, int length = -1);
diff --git a/src/xprofiler.cc b/src/xprofiler.cc
index 23f7f07..3c316e5 100644
--- a/src/xprofiler.cc
+++ b/src/xprofiler.cc
@@ -15,43 +15,42 @@ using Nan::Set;
 using v8::FunctionTemplate;
 using v8::String;
 
+NODE_C_CTOR(Main) {
+  // init global variables
+  InitOnceLoadTime();
+  InitOnceLogger();
+}
+
 #define CREATE_JS_BINDING(js_func, native_func)       \
   Set(target, New<String>(#js_func).ToLocalChecked(), \
-      GetFunction(New<FunctionTemplate>(native_func)).ToLocalChecked());
+      GetFunction(New<FunctionTemplate>(native_func)).ToLocalChecked())
 
 NAN_MODULE_INIT(Initialize) {
-  // init global variables
-  InitGlobalVariables();
-
-  // init logger
-  int rc = InitLogger();
-  if (rc != 0) return;
-
   // config
-  CREATE_JS_BINDING(configure, Configure)
-  CREATE_JS_BINDING(getConfig, GetConfig)
+  CREATE_JS_BINDING(configure, Configure);
+  CREATE_JS_BINDING(getConfig, GetConfig);
 
   // js logger
-  CREATE_JS_BINDING(info, JsInfo)
-  CREATE_JS_BINDING(error, JsError)
-  CREATE_JS_BINDING(debug, JsDebug)
+  CREATE_JS_BINDING(info, JsInfo);
+  CREATE_JS_BINDING(error, JsError);
+  CREATE_JS_BINDING(debug, JsDebug);
 
   // performance log
-  CREATE_JS_BINDING(runLogBypass, RunLogBypass)
+  CREATE_JS_BINDING(runLogBypass, RunLogBypass);
 
   // commands listener
-  CREATE_JS_BINDING(checkSocketPath, CheckSocketPath)
-  CREATE_JS_BINDING(runCommandsListener, RunCommandsListener)
+  CREATE_JS_BINDING(checkSocketPath, CheckSocketPath);
+  CREATE_JS_BINDING(runCommandsListener, RunCommandsListener);
 
   // set hooks
-  CREATE_JS_BINDING(setHooks, SetHooks)
+  CREATE_JS_BINDING(setHooks, SetHooks);
 
   // http status
-  CREATE_JS_BINDING(addLiveRequest, AddLiveRequest)
-  CREATE_JS_BINDING(addCloseRequest, AddCloseRequest)
-  CREATE_JS_BINDING(addSentRequest, AddSentRequest)
-  CREATE_JS_BINDING(addRequestTimeout, AddRequestTimeout)
-  CREATE_JS_BINDING(addHttpStatusCode, AddHttpStatusCode)
+  CREATE_JS_BINDING(addLiveRequest, AddLiveRequest);
+  CREATE_JS_BINDING(addCloseRequest, AddCloseRequest);
+  CREATE_JS_BINDING(addSentRequest, AddSentRequest);
+  CREATE_JS_BINDING(addRequestTimeout, AddRequestTimeout);
+  CREATE_JS_BINDING(addHttpStatusCode, AddHttpStatusCode);
 }
 
 // TODO(legendecas): declare context aware when ready.