diff --git a/src/HAMqtt.cpp b/src/HAMqtt.cpp
index 7ff1a5a..af3a35b 100644
--- a/src/HAMqtt.cpp
+++ b/src/HAMqtt.cpp
@@ -60,7 +60,8 @@ HAMqtt::HAMqtt(
     HADevice& device,
     uint8_t maxDevicesTypesNb
 ) :
-    _mqtt(new PubSubClient(netClient)),
+    _mqttStorage(netClient),
+    _mqtt(&_mqttStorage),
     HAMQTT_INIT
 {
     _instance = this;
@@ -71,9 +72,11 @@ HAMqtt::~HAMqtt()
 {
     delete[] _devicesTypes;
 
+#ifdef ARDUINOHA_TEST
     if (_mqtt) {
         delete _mqtt;
     }
+#endif
 
     _instance = nullptr;
 }
diff --git a/src/HAMqtt.h b/src/HAMqtt.h
index e0b3188..915f8ea 100644
--- a/src/HAMqtt.h
+++ b/src/HAMqtt.h
@@ -14,7 +14,7 @@
 #ifdef ARDUINOHA_TEST
 class PubSubClientMock;
 #else
-class PubSubClient;
+#include <PubSubClient.h>
 #endif
 
 #if defined(__AVR_ATmega328P__) || defined(__AVR_ATmega168__)
@@ -417,7 +417,10 @@ private:
 #ifdef ARDUINOHA_TEST
     PubSubClientMock* _mqtt;
 #else
-    /// Instance of the PubSubClient class. It's initialized in the constructor.
+    /// Storage for the PubSubClient instance used in production builds.
+    PubSubClient _mqttStorage;
+
+    /// Pointer to the active MQTT client implementation.
     PubSubClient* _mqtt;
 #endif
 
diff --git a/src/device-types/HABaseDeviceType.cpp b/src/device-types/HABaseDeviceType.cpp
index 17583e3..d5ce93c 100644
--- a/src/device-types/HABaseDeviceType.cpp
+++ b/src/device-types/HABaseDeviceType.cpp
@@ -20,6 +20,11 @@ HABaseDeviceType::HABaseDeviceType(
     }
 }
 
+HABaseDeviceType::~HABaseDeviceType()
+{
+    destroySerializer();
+}
+
 void HABaseDeviceType::setAvailability(bool online)
 {
     _availability = (online ? AvailabilityOnline : AvailabilityOffline);
diff --git a/src/device-types/HABaseDeviceType.h b/src/device-types/HABaseDeviceType.h
index 0d6fa32..8514bce 100644
--- a/src/device-types/HABaseDeviceType.h
+++ b/src/device-types/HABaseDeviceType.h
@@ -37,6 +37,8 @@ public:
         const char* uniqueId
     );
 
+    virtual ~HABaseDeviceType();
+
     /**
      * Returns unique ID of the device type.
      */