diff --git a/CMakeLists.txt b/CMakeLists.txt
index 9d2faf19..e10acc20 100755
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -10,14 +10,17 @@ IF (CMAKE_SYSTEM_NAME MATCHES "Linux")
         stop()
     elseif(version LESS 7.1.0)
         set(CMAKE_CXX_STD_FLAGS c++14)
+        set(CXX_STD 14)
         MESSAGE(STATUS "c++14")
     else()
         set(CMAKE_CXX_STD_FLAGS c++17)
+        set(CXX_STD 17)
         MESSAGE(STATUS "c++17")
     endif()
 else()
 #MacOS use c++17
     set(CMAKE_CXX_STD_FLAGS c++17)
+    set(CXX_STD 17)
 endif()
 
 include_directories(${PROJECT_SOURCE_DIR}/trantor ${PROJECT_SOURCE_DIR}/lib/inc ${PROJECT_SOURCE_DIR}/orm_lib/inc)
@@ -131,7 +134,7 @@ SET(CONFIG_HEADER "${PROJECT_SOURCE_DIR}/config.h")
 file(WRITE "${CONFIG_HEADER}" "#pragma once\n")
 
 file(APPEND "${CONFIG_HEADER}" "#include <trantor/utils/config.h>\n")
-
+file(APPEND "${CONFIG_HEADER}" "#define CXX_STD " ${CXX_STD} "\n")
 if(USE_ORM)
     file(APPEND "${CONFIG_HEADER}" "#define USE_ORM 1\n")
     if(PostgreSQL_FOUND)
diff --git a/lib/src/HttpServer.cc b/lib/src/HttpServer.cc
index b149d7ee..a497ed73 100755
--- a/lib/src/HttpServer.cc
+++ b/lib/src/HttpServer.cc
@@ -88,8 +88,11 @@ void HttpServer::onConnection(const TcpConnectionPtr &conn)
             {
                 _disconnectWebsocketCallback(requestParser->webSocketConn());
             }
-            //conn->getMutableContext()->reset();   reset() is in c++17
-            conn->setContext(0);
+#if (CXX_STD > 14)
+            conn->getMutableContext()->reset(); //reset(): since c++17
+#else
+            conn->getMutableContext()->clear();
+#endif
         }
     }
     _connectionCallback(conn);