diff --git a/HEADS b/HEADS
index 5dde0b7..f613214 100644
--- a/HEADS
+++ b/HEADS
@@ -1 +1 @@
-{"engine": {"master": "09e13d255cee057e788b2acceec896a2e86df615"}}
\ No newline at end of file
+{"engine": {"master": "06cd3e0f6b6081434af6bd9fcf154553a45941c6"}}
\ No newline at end of file
diff --git a/app/rdn_application.cpp b/app/rdn_application.cpp
index 2adb536..ad48e2b 100644
--- a/app/rdn_application.cpp
+++ b/app/rdn_application.cpp
@@ -39,6 +39,10 @@ void RDNApplication::setup_middleware() {
 void RDNApplication::migrate() {
 }
 
+void RDNApplication::mqtt_sensor_callback(const std::string &client_id, const std::vector<uint8_t> &data) {
+	printf("%s\n", client_id.c_str());
+}
+
 RDNApplication::RDNApplication() :
 		Application() {
 }
diff --git a/app/rdn_application.h b/app/rdn_application.h
index aa3ee44..0f7b08c 100644
--- a/app/rdn_application.h
+++ b/app/rdn_application.h
@@ -1,6 +1,8 @@
 #ifndef RDN_APPLICATION_H
 #define RDN_APPLICATION_H
 
+#include <vector>
+
 #include "core/application.h"
 #include "core/object.h"
 
@@ -17,6 +19,8 @@ public:
 
     virtual void migrate();
 
+    void mqtt_sensor_callback(const std::string &client_id, const std::vector<uint8_t> &data);
+
     RDNApplication();
     ~RDNApplication();
 
diff --git a/main.cpp b/main.cpp
index a1e851d..4e05c9f 100644
--- a/main.cpp
+++ b/main.cpp
@@ -83,6 +83,7 @@ int main(int argc, char **argv) {
 
 	MQTTServer *mqtt_server = new MQTTServer();
 	mqtt_server->initialize();
+	mqtt_server->add_local_session("a/b", [](const std::string &client_id, const std::vector<uint8_t> &data, void* obj){ reinterpret_cast<RDNApplication*>(obj)->mqtt_sensor_callback(client_id, data); }, app);
 
 	if (!migrate) {
 		printf("Initialized!\n");