diff --git a/src/core/AsyncClient/RequestHandler.h b/src/core/AsyncClient/RequestHandler.h
index 130d4403..4ad37a67 100644
--- a/src/core/AsyncClient/RequestHandler.h
+++ b/src/core/AsyncClient/RequestHandler.h
@@ -9,6 +9,8 @@
 #include "./core/Utils/StringUtil.h"
 #include "./core/Utils/URL.h"
 #include "./core/Utils/Base64.h"
+#include "./core/AsyncClient/ConnectionHandler.h"
+#include "./core/Auth/Token/AppToken.h"
 #if defined(ENABLE_ASYNC_TCP_CLIENT)
 #include "./core/AsyncClient/AsyncTCPConfig.h"
 #endif
diff --git a/src/core/AsyncClient/ResponseHandler.h b/src/core/AsyncClient/ResponseHandler.h
index bf63beee..a75da1e8 100644
--- a/src/core/AsyncClient/ResponseHandler.h
+++ b/src/core/AsyncClient/ResponseHandler.h
@@ -4,6 +4,7 @@
 #include <Arduino.h>
 #include <Client.h>
 #include "./core/Error.h"
+#include "./core/AsyncClient/ConnectionHandler.h"
 #include "./core/AsyncClient/RequestHandler.h"
 #include "./core/Utils/StringUtil.h"
 #if defined(ENABLE_ASYNC_TCP_CLIENT)
diff --git a/src/core/AsyncClient/SlotOptions.h b/src/core/AsyncClient/SlotOptions.h
index 9f394b2f..63581381 100644
--- a/src/core/AsyncClient/SlotOptions.h
+++ b/src/core/AsyncClient/SlotOptions.h
@@ -3,6 +3,8 @@
 
 #include "./core/Auth/Token/AppToken.h"
 
+using namespace firebase_ns;
+
 struct slot_options_t
 {
 public: