diff --git a/gateway/include/Protocol_1.h b/gateway/include/Protocol_1.h
index ccbc329..6d9dd85 100644
--- a/gateway/include/Protocol_1.h
+++ b/gateway/include/Protocol_1.h
@@ -27,10 +27,9 @@ public:
         rcSwitch["raw_value"] = value;
     }
 
-    static char* buildId(const char* group, const unsigned char channel) {
-        char* uId = new char[30];
+    static std::string buildId(const char* group, const unsigned char channel) {
+        char uId[30];
         sprintf(uId, "%s_%d", group, channel);
-        return uId;
+        return std::string{ uId };
     }
-
 };
diff --git a/gateway/include/Protocol_2.h b/gateway/include/Protocol_2.h
index f618898..589154e 100644
--- a/gateway/include/Protocol_2.h
+++ b/gateway/include/Protocol_2.h
@@ -33,16 +33,4 @@ public:
         }
     }
 
-    static char* buildId(const char* id) {
-        char* uId = new char[30];
-        sprintf(uId, "%s", id);
-        return uId;
-    }
-
-    static char* buildId(unsigned int id) {
-        char* uId = new char[30];
-        sprintf(uId, "%d", id);
-        return uId;
-    }
-
 };
\ No newline at end of file
diff --git a/gateway/include/devices.h b/gateway/include/devices.h
index 6ae8b46..46d395e 100644
--- a/gateway/include/devices.h
+++ b/gateway/include/devices.h
@@ -7,66 +7,66 @@
 using namespace Ha;
 
 DeviceConfig* gatewayDevice = (new DeviceConfig{MAIN_DEVICE_ID})->withName("RC Gateway")->withManufacturer("Adafruit")->withModel("Huzzah Esp8266");
-DeviceConfig* atTinyDevice = (new DeviceConfig{})->withManufacturer("Atmel")->withModel("AtTiny85")->withParent(gatewayDevice);
 
-struct OilTankRoomSensorBuilder {
-    static Sensor* build(const char* id) {
-        auto device = (new DeviceConfig{*atTinyDevice})->withName("Oil tank room")->withArea("Basement");
-        device->id = id;
-        Sensor* sensor = (new Ha::TemperatureSensor(id))->asDevice(device);
-        (new VoltageSensor{sensor->id, "Battery voltage", "{{ value_json.sensor.diagnostic.voltage }}"})->ofDevice((id));
-        (new BatterySensor{sensor->id, "Battery level", "{{ ((states('sensor.oil_tank_room_battery_voltage')|float-2.5)|round(2)*100/2)|int }}"})->ofDevice(id);
-        return sensor;
-    }
-};
-
-struct OilTankSensor : Sensor {
-    OilTankSensor(const char* id) : Sensor("Depth", id) {
-        deviceClass = "distance";
-        unitMeasure = "cm";
-        valueTemplate = "{{ value_json.sensor.value }}";
-    }
-};
-
-struct OilTankLevelSensor : Sensor {
-    OilTankLevelSensor(const char* id) : Sensor("Level", id) {
-        unitMeasure = "%";
-        valueTemplate = "{{ 100 - ((value_json.sensor.value-7)|float*100/110)|round(2) }}";
+namespace OilTank {
+    Sensor* buildRoomSensor(const char* id) {
+        auto device = DeviceConfig::create(id)
+            ->withName("Oil tank room")
+            ->withManufacturer("Atmel")
+            ->withModel("AtTiny85")
+            ->withArea("Basement")
+            ->withParent(gatewayDevice);
+        return Builder<TemperatureSensor>::instance(id)
+            .asDevice(device)
+            .withValueTemplate("{{ value_json.sensor.temperature }}")
+            .withDiagnostic(new VoltageSensor{id, "Battery voltage", "{{ value_json.sensor.diagnostic.voltage }}"})
+            .withDiagnostic(new BatterySensor{id, "Battery level", "{{ ((states('sensor.oil_tank_room_battery_voltage')|float-2.5)|round(2)*100/2)|int }}"})
+            .build();
     }
 
-    void buildUniqueId(char* uniqueId) override {
-        sprintf(uniqueId, "level_%s", id);
+    Sensor* buildTankSensor(const char* id) {
+        auto device = DeviceConfig::create(id)
+            ->withName("Oil tank")
+            ->withManufacturer("Arduino")
+            ->withModel("Pro Mini")
+            ->withArea("Basement")
+            ->withParent(gatewayDevice);
+        return Builder<Sensor>::instance(new Sensor{ "Depth", id })
+            .asDevice(device)
+            .withDeviceClass("distance")
+            .withUnitMseasure("cm")
+            .withValueTemplate("{{ value_json.sensor.value }}")
+            .withSecondary(
+                Builder<Sensor>::instance(new Sensor{ "Level", id })
+                .withUnitMseasure("%")
+                .withValueTemplate("{{ 100 - ((value_json.sensor.value-7)|float*100/110)|round(2) }}")
+                .build()
+            )
+            .withDiagnostic(new VoltageSensor{id, "Battery voltage", "{{ value_json.sensor.diagnostic.voltage }}"})
+            .withDiagnostic(new BatterySensor{id, "Battery level", "{{ ((states('sensor.oil_tank_battery_voltage')|float-3.6)|round(2)*100/1.6)|int }}"})
+            .build();
     }
-        
-    void buildConfigTopic() override {
-        sprintf(configTopic, "homeassistant/%s/%s/level_%s/config", type, MAIN_DEVICE_ID, id);
-    }
-};
-
-struct OilSensorBuilder {
-    static Sensor* build(const char* id) {
-        auto device = (new DeviceConfig{*atTinyDevice})->withName("Oil tank")->withArea("Basement");
-        device->id = id;
-        Sensor* sensor = (new OilTankSensor(id))->asDevice(device);
-        (new OilTankLevelSensor(sensor->id))->ofDevice(id);
-        (new VoltageSensor{id, "Battery voltage", "{{ value_json.sensor.diagnostic.voltage }}"})->ofDevice(id);
-        (new BatterySensor{id, "Battery level", "{{ ((states('sensor.oil_tank_battery_voltage')|float-3.6)|round(2)*100/1.6)|int }}"})->ofDevice(id);
-        return sensor;
-    }
-};
+}
 
 struct PollinSwitch : Switch {
     const char* group;
     unsigned char channel;
 
     PollinSwitch(const char* name, const char* group, const unsigned char channel, const char* area = nullptr)
-        : Switch(name, Protocol_1::buildId(group, channel)), group(group), channel(channel) {
-        asDevice((new DeviceConfig{id})->withName(name)->withManufacturer("Pollin")->withArea(area)->withParent(gatewayDevice));
+        : Switch(name, [group, channel]{
+                // copy id from string into a new pointer, to avoid memory leaks
+                string s = Protocol_1::buildId(group, channel);
+                char* uId = new char[s.length() + 1];
+                strcpy(uId, s.c_str());
+                return uId;
+            }()), group(group), channel(channel) {
+        mainDevice = (new DeviceConfig{id})->withName(name)->withManufacturer("Pollin")->withArea(area)->withParent(gatewayDevice);
+        deviceClass = "outlet";
         p1Switches.insert({ string(id), this });
     }
 
     void onCommand(const char* msg) override {
-        (String{ "ON" }.equals(msg)) ? mySwitch.switchOn(group, channel) : mySwitch.switchOff(group, channel);
+        strcmp("ON", msg) == 0 ? mySwitch.switchOn(group, channel) : mySwitch.switchOff(group, channel);
         publisher(stateTopic, msg);
     }
 
@@ -80,7 +80,8 @@ struct EasyHomeSwitch : Switch {
         : Switch(name, id) {
         memcpy(&this->on[4], on, 4 * sizeof(unsigned long));
         memcpy(&this->off[4], off, 4 * sizeof(unsigned long));
-        asDevice((new DeviceConfig{id})->withName(name)->withManufacturer("Intertek")->withModel("Easy Home")->withArea(area)->withParent(gatewayDevice));
+        mainDevice = (new DeviceConfig{id})->withName(name)->withManufacturer("Intertek")->withModel("Easy Home")->withArea(area)->withParent(gatewayDevice);
+        deviceClass = "outlet";
         for (int i = 0; i < 8; i++) {
             onSwitches.insert({ this->on[i], this });
             offSwitches.insert({ this->off[i], this });
@@ -89,7 +90,7 @@ struct EasyHomeSwitch : Switch {
 
     void onCommand(const char* msg) override {
         mySwitch.setProtocol(4);
-        String{ "ON" }.equals(msg) ? mySwitch.send(on[4], 24) : mySwitch.send(off[4], 24);
+        strcmp("ON", msg) == 0 ? mySwitch.send(on[4], 24) : mySwitch.send(off[4], 24);
         publisher(stateTopic, msg);
     }
 };
diff --git a/gateway/include/ha.h b/gateway/include/ha.h
index 61515cc..c8a4f33 100644
--- a/gateway/include/ha.h
+++ b/gateway/include/ha.h
@@ -8,6 +8,7 @@
 
 namespace Ha {
     uint16_t (*publisher)(const char* topic, const char* message);
+    typedef void (*onMessage)(const char* msg);
 
     struct DeviceConfig {
         const char* id = nullptr;
@@ -17,9 +18,11 @@ namespace Ha {
         const char* area = nullptr;
         DeviceConfig* parent = nullptr;
 
-        DeviceConfig() {}
         DeviceConfig(const char* id) : id(id) {}
-        DeviceConfig(DeviceConfig& d) : id(d.id), name(d.name), model(d.model), manufacturer(d.manufacturer), area(d.area), parent(d.parent) {}
+
+        static DeviceConfig* create(const char* id) {
+            return new DeviceConfig{ id };
+        }
 
         void buildConfig(JsonDocument& jsonDoc) {
             JsonObject device = jsonDoc.createNestedObject("device");
@@ -72,18 +75,15 @@ namespace Ha {
             components.add(this);
         }
 
-        virtual void buildUniqueId(char* uniqueId) = 0;
-        
+        virtual void buildUniqueId(char* uniqueId) {
+            sprintf(uniqueId, "%s_%s", MAIN_DEVICE_ID, id);
+        }
+
         virtual void buildConfigTopic() {
-            if (String{"diagnostic"}.equals(entityCategory) && deviceClass) {
-                sprintf(configTopic, "homeassistant/%s/%s/%s_%s/config", type, MAIN_DEVICE_ID, deviceClass, id);
-            } else {
-                sprintf(configTopic, "homeassistant/%s/%s/%s/config", type, MAIN_DEVICE_ID, id);
-            }
+            sprintf(configTopic, "homeassistant/%s/%s/%s/config", type, MAIN_DEVICE_ID, id);
         }
 
         virtual void buildConfig(JsonDocument& jsonDoc) {
-            buildConfigTopic();
             if (mainDevice) mainDevice->buildConfig(jsonDoc);
             if (entityCategory) jsonDoc["entity_category"] = entityCategory;
             if (deviceClass) jsonDoc["device_class"] = deviceClass;
@@ -91,52 +91,118 @@ namespace Ha {
             char uniqueId[50];
             buildUniqueId(uniqueId);
             jsonDoc["unique_id"] = uniqueId;
+            buildConfigTopic();
+        }
+
+        void publishConfig() {
+            StaticJsonDocument<JSON_SIZE> jsonDoc;
+            buildConfig(jsonDoc);
+
+            char message[JSON_SIZE];
+            serializeJson(jsonDoc, message);
+
+            publisher(configTopic, message);
+        }
+
+        void publishCleanupConfig() {
+            publisher(configTopic, "");
         }
     };
-
-    template <class T>
-    struct EntityConfig : Component {
-
-        EntityConfig(const char* name, const char* id, const char* type) : Component(name, id, type) {
-        }
-
-        T* asDevice(DeviceConfig* deviceConfig) {
-            mainDevice = deviceConfig;
-            return static_cast<T*>(this);
-        }
-
-        T* ofDevice(const char* id) {
-            mainDevice = new DeviceConfig{id};
-            return static_cast<T*>(this);
-        }
-    };
-    
     List<Component> Component::components;
 
-    template <class T>
-    struct Command : EntityConfig<T> {
-        char commandTopic[TOPIC_SIZE];
+    struct AbstractBuilder {
+        static List<AbstractBuilder> builders;
 
-        Command(const char* name, const char* id, const char* type) : EntityConfig<T>(name, id, type) {
-            sprintf(commandTopic, "homeassistant/%s/%s/%s", type, MAIN_DEVICE_ID, id);
+        AbstractBuilder() {
+            builders.add(this);
         }
 
-        void buildUniqueId(char* uniqueId) override {
-            sprintf(uniqueId, "%s_%s", MAIN_DEVICE_ID, this->id);
+        static void deleteAll() {
+            List<AbstractBuilder>::exec(builders, [](AbstractBuilder* builder)
+                                        { delete builder; });
+        }
+    };
+    List<AbstractBuilder> AbstractBuilder::builders;
+
+    template <class T>
+    struct Builder : AbstractBuilder {
+        T* cmp;
+
+        Builder(T* cmp) :  AbstractBuilder(), cmp(cmp) {}
+
+        Builder(const char* id) : AbstractBuilder() {
+            cmp = new T{id};
+        }
+
+        static Builder& instance(T* c) {
+            return *(new Builder<T>(c));
+        }
+
+        static Builder& instance(const char* id) {
+            return *(new Builder<T>(id));
+        }
+
+        T* build() {
+            return static_cast<T*>(cmp);
+        }
+
+        Builder& withDeviceClass(const char* value) {
+            cmp->deviceClass = value;
+            return *this;
+        }
+
+        Builder& withUnitMseasure(const char* value) {
+            cmp->unitMeasure = value;
+            return *this;
+        }
+
+        Builder& withValueTemplate(const char* value) {
+            cmp->valueTemplate = value;
+            return *this;
+        }
+
+        Builder& withSecondary(Component* c) {
+            c->mainDevice = new DeviceConfig{ cmp->id };
+            return *this;
+        }
+
+        Builder& withDiagnostic(Component* c) {
+            c->entityCategory = "diagnostic";
+            c->mainDevice = new DeviceConfig{ cmp->id };
+            return *this;
+        }
+
+        Builder& asDevice(DeviceConfig* deviceConfig) {
+            cmp->mainDevice = deviceConfig;
+            return *this;
+        }
+    };
+
+    struct Command : Component {
+        char commandTopic[TOPIC_SIZE];
+        onMessage f;
+        static unordered_map<string, Command*> mapCommands;
+
+        Command(const char* name, const char* id, const char* type, onMessage f) : Component(name, id, type), f(f) {
+            sprintf(commandTopic, "homeassistant/%s/%s/%s/set", type, MAIN_DEVICE_ID, id);
+            mapCommands.insert({ string(commandTopic), this });
+        }
+
+        virtual void onCommand(const char* msg) {
+            if (f) f(msg);
         }
 
         void buildConfig(JsonDocument& jsonDoc) override {
-            EntityConfig<T>::buildConfig(jsonDoc);
+            Component::buildConfig(jsonDoc);
             jsonDoc["command_topic"] = commandTopic;
         }
 
     };
+    unordered_map<string, Command*> Command::mapCommands;
 
-    typedef void (*onMessage)(const char* msg);
-    struct Button : Command<Button> {
-        onMessage f;
+    struct Button : Command {
 
-        Button(const char* name, const char* id, onMessage f) : Command(name, id, "button"), f(f) {}
+        Button(const char* name, const char* id, onMessage f = nullptr) : Command(name, id, "button", f) {}
 
     };
 
@@ -150,18 +216,13 @@ namespace Ha {
         }
     };
 
-    struct Switch : Command<Switch>, StateConfig<Switch> {
+    struct Switch : Command, StateConfig<Switch> {
 
-        virtual void onCommand(const char* msg){}
-
-        Switch(const char* name, const char* id) : Command(name, id, "switch") {
-            sprintf(commandTopic, "homeassistant/%s/%s/%s/set", type, MAIN_DEVICE_ID, id);
-        }
+        Switch(const char* name, const char* id, onMessage f = nullptr) : Command(name, id, "switch", f) {}
 
         void buildConfig(JsonDocument& jsonDoc) override {
             Command::buildConfig(jsonDoc);
             jsonDoc["name"] = nullptr;
-            jsonDoc["device_class"] = "outlet";
             // jsonDoc["retain"] = true;
             if (stateTopic[0]) jsonDoc["state_topic"] = stateTopic;
         }
@@ -171,20 +232,36 @@ namespace Ha {
         }
     };
 
-    struct Sensor : EntityConfig<Sensor>, StateConfig<Sensor> {
+    struct Sensor : Component, StateConfig<Sensor> {
         const char* unitMeasure = nullptr;
         const char* valueTemplate = nullptr;
 
-        Sensor(const char* name, const char* id) : EntityConfig(name, Protocol_2::buildId(id), "sensor") {
+        Sensor() : Component(name, id, "sensor") {
+            withStateTopic();
+        }
+
+        Sensor(const char* name, const char* id) : Component(name, id, "sensor") {
             withStateTopic();
         }
 
         void buildUniqueId(char* uniqueId) override {
-            sprintf(uniqueId, "%s_%s", deviceClass, id);
+            if (deviceClass) {
+                sprintf(uniqueId, "%s_%s_%s", MAIN_DEVICE_ID, deviceClass, id);
+            } else {
+                Component::buildUniqueId(uniqueId);
+            }
+        }
+
+        void buildConfigTopic() override {
+            if (deviceClass) {
+                sprintf(configTopic, "homeassistant/%s/%s/%s_%s/config", type, MAIN_DEVICE_ID, deviceClass, id);
+            } else {
+                Component::buildConfigTopic();
+            }
         }
 
         void buildConfig(JsonDocument& jsonDoc) override {
-            EntityConfig::buildConfig(jsonDoc);
+            Component::buildConfig(jsonDoc);
             if (unitMeasure) jsonDoc["unit_of_measurement"] = unitMeasure;
             if (valueTemplate) jsonDoc["value_template"] = valueTemplate;
             jsonDoc["state_topic"] = stateTopic;
@@ -193,17 +270,15 @@ namespace Ha {
     };
 
     struct TemperatureSensor : Sensor {
-        TemperatureSensor(const char* id) : Sensor("Temperature", id) {
+        TemperatureSensor(const char* id, const char* name = "Temperature") : Sensor(name, id) {
             deviceClass = "temperature";
             unitMeasure = "°C";
-            valueTemplate = "{{ value_json.sensor.temperature }}";
         }
     };
 
     struct VoltageSensor : Sensor {
         VoltageSensor(const char* id, const char* name, const char* valueTemplate) : Sensor(name, id) {
             this->valueTemplate = valueTemplate;
-            entityCategory = "diagnostic";
             deviceClass = "voltage";
             unitMeasure = "V";
         }
@@ -212,27 +287,24 @@ namespace Ha {
     struct BatterySensor : Sensor {
        BatterySensor(const char* id, const char* name, const char* valueTemplate) : Sensor(name, id) {
             this->valueTemplate = valueTemplate;
-            entityCategory = "diagnostic";
             deviceClass = "battery";
             unitMeasure = "%";
         }
     };
 
     struct HumiditySensor : Sensor {
-        HumiditySensor(const char* name, const char* id) : Sensor(name, id) {
-            name = "Humidity";
+        HumiditySensor(const char* id, const char* name = "Humidity") : Sensor(name, id) {
             deviceClass = "humidity";
             unitMeasure = "%";
-            valueTemplate = "{{ value_json.sensor.humidity }}";
+            // valueTemplate = "{{ value_json.sensor.humidity }}";
         }
     };
 
     struct PressureSensor : Sensor {
-        PressureSensor(const char* name, const char* id) : Sensor(name, id) {
-            name = "Pressure";
+        PressureSensor(const char* id, const char* name = "Pressure") : Sensor(name, id) {
             deviceClass = "pressure";
             unitMeasure = "hPa";
-            valueTemplate = "{{ value_json.sensor.pressure }}";
+            // valueTemplate = "{{ value_json.sensor.pressure }}";
         }
     };
 }
diff --git a/gateway/include/huzzah.h b/gateway/include/huzzah.h
index b286363..317582b 100644
--- a/gateway/include/huzzah.h
+++ b/gateway/include/huzzah.h
@@ -48,44 +48,46 @@ namespace Board {
 		ts.execute();
 	}
 
+	void parseSwitches(JsonDocument& jsonDoc) {
+		JsonObjectConst rcSwitch = jsonDoc["rcSwitch"];
+		switch ((unsigned int)rcSwitch["protocol"]) {
+		case 1: {
+			string id = Protocol_1::buildId((const char*)rcSwitch["group"], (int)rcSwitch["channel"]);
+			Ha::Switch* el = p1Switches[id];
+			if (el) el->publishState((bool)rcSwitch["state"]);
+			break;
+		}
+		case 2:
+			break;
+		default: {
+			unsigned long value = rcSwitch["value"];
+			auto range = onSwitches.equal_range(value);
+			for_each(range.first, range.second, [](mapswitches::value_type& x){
+				x.second->publishState(true);
+			});
+			range = offSwitches.equal_range(value);
+			for_each(range.first, range.second, [](mapswitches::value_type& x){
+				x.second->publishState(false);
+			});
+		}
+		}
+	}
+
+	void parseSensors(JsonDocument& jsonDoc, char* message) {
+		JsonObjectConst json = jsonDoc["sensor"];
+		string id = to_string((unsigned int)json["id"]);
+		char stateTopic[TOPIC_SIZE];
+		sprintf(stateTopic, "homeassistant/sensor/%s/%s/state", MAIN_DEVICE_ID, id.c_str());
+		Mqtt::publish(stateTopic, message);
+
+	}
+
 	void publishResponse(JsonDocument& jsonDoc) {
         char message[255];
         serializeJson(jsonDoc, message);
 		Mqtt::publish("homeassistant/sensor/rc-gateway/raw", message);
-		if (jsonDoc.containsKey("rcSwitch")) {
-			JsonObjectConst rcSwitch = jsonDoc["rcSwitch"];
-			switch ((unsigned int)rcSwitch["protocol"]) {
-			case 1: {
-				// buildId returns a new pointer, should it be deleted, or string will take care of it?
-				string id = Protocol_1::buildId((const char*)rcSwitch["group"], (int)rcSwitch["channel"]);
-				Ha::Switch* el = p1Switches[id];
-				if (el != nullptr) {
-					el->publishState((bool)rcSwitch["state"]);
-				}
-				break;
-			}
-			case 2:
-				break;
-			default: {
-				unsigned long value = rcSwitch["value"];
-				auto range = onSwitches.equal_range(value);
-				for_each(range.first, range.second, [](mapswitches::value_type& x){
-					x.second->publishState(true);
-				});
-				range = offSwitches.equal_range(value);
-				for_each(range.first, range.second, [](mapswitches::value_type& x){
-					x.second->publishState(false);
-				});
-			}
-			}
-		}
-		if (jsonDoc.containsKey("sensor")) {
-			JsonObjectConst json = jsonDoc["sensor"];
-			string id = Protocol_2::buildId((unsigned int)json["id"]);
-			char stateTopic[TOPIC_SIZE];
-			sprintf(stateTopic, "homeassistant/sensor/%s/%s/state", MAIN_DEVICE_ID, id.c_str());
-			Mqtt::publish(stateTopic, message);
-		}
+		if (jsonDoc.containsKey("rcSwitch")) parseSwitches(jsonDoc);
+		if (jsonDoc.containsKey("sensor")) parseSensors(jsonDoc, message);
 	}
 
 	void handleJsonError(JsonDocument& jsonError) {
diff --git a/gateway/include/mqtt.h b/gateway/include/mqtt.h
index 96957cb..bfa5bcc 100644
--- a/gateway/include/mqtt.h
+++ b/gateway/include/mqtt.h
@@ -12,12 +12,11 @@ namespace Mqtt {
 
     AsyncMqttClient client;
 
-    void publishInit();
-    void disconnect();
     Task tReConnect(5 * TASK_MINUTE, TASK_FOREVER, []() {
         Serial.println("Connecting to MQTT...");
         client.connect();
     }, &ts);
+    void publishInit();
     Task tPublishInit(TASK_IMMEDIATE, TASK_ONCE, publishInit, &ts);
 
     const char* mainTopic = "homeassistant/+/rc-gateway/#";
@@ -31,68 +30,44 @@ namespace Mqtt {
         return client.publish(topic, 0, true, message);
     }
 
-    Ha::Button* buttons[] = {
-        (new Ha::Button{"Restart", "restart",
+    Command* commands[] = {
+        Builder<Button>::instance(new Button{"Restart", "restart",
             [](const char* msg) {
-                if (String { "PRESS" }.equals(msg)) ESP.restart();
+                if (strcmp("PRESS", msg) == 0) ESP.restart();
             }
-        })->asDevice(gatewayDevice)
-    };
-
-    Ha::Switch* switches[] = {
+        }).asDevice(gatewayDevice).build(),
+        (new EasyHomeSwitch{"FritzBox", "easy_home_a", (unsigned long[4]) { 4483136, 4626800, 4661552, 4819632 }, (unsigned long[4]) { 4326544, 4537104, 4767520, 4972704 }, "Basement"})->withStateTopic(),
+        (new EasyHomeSwitch{"Outside", "easy_home_b", (unsigned long[4]) { 4483140, 4626804, 4661556, 4819636 }, (unsigned long[4]) { 4326548, 4537108, 4767524, 4972708 }, "Basement"})->withStateTopic(),
         (new PollinSwitch{"Meeting sensor", "00001", 1, "Dining room"})->withStateTopic(),
         (new PollinSwitch{"Fire Tv", "00001", 2, "Living room"})->withStateTopic(),
         (new PollinSwitch{"Diningroom player", "00001", 3, "Dining room"})->withStateTopic(),
-        (new PollinSwitch{"Train", "11111", 4, "Playroom"})->withStateTopic(),
-        (new EasyHomeSwitch{"FritzBox", "easy_home_a", (unsigned long[4]) { 4483136, 4626800, 4661552, 4819632 }, (unsigned long[4]) { 4326544, 4537104, 4767520, 4972704 }, "Basement"})->withStateTopic(),
-        (new EasyHomeSwitch{"Outside", "easy_home_b", (unsigned long[4]) { 4483140, 4626804, 4661556, 4819636 }, (unsigned long[4]) { 4326548, 4537108, 4767524, 4972708 }, "Basement"})->withStateTopic()
+        (new PollinSwitch{"Train", "11111", 4, "Playroom"})->withStateTopic()
     };
 
-    Ha::Sensor* sensors[] = {
-        OilTankRoomSensorBuilder::build("4"),
-        OilSensorBuilder::build("7")
+    Sensor* sensors[] = {
+        OilTank::buildRoomSensor("4"),
+        OilTank::buildTankSensor("7")
     };
 
-    void publishComponentConfig(Ha::Component& component) {
-        StaticJsonDocument<JSON_SIZE> jsonDoc;
-        component.buildConfig(jsonDoc);
-
-        char message[JSON_SIZE];
-        serializeJson(jsonDoc, message);
-
-        publish(component.configTopic, message);
-    }
-
     void publishInit() {
         Ha::publisher = publish;
-        for (List<Ha::Component>::Container* c = Ha::Component::components.first; c; c = c->next) {
-            publishComponentConfig(*c->t);
-        }
+        List<Component>::exec(Component::components, [](Component* c)
+                              { c->publishConfig(); });
+        AbstractBuilder::deleteAll();
         ts.deleteTask(tPublishInit);
     }
 
     void publishCleanupConfig() {
-        for (List<Ha::Component>::Container* c = Ha::Component::components.first; c; c = c->next) {
-            publish(c->t->configTopic, "");
-        }
+        List<Component>::exec(Component::components, [](Component* c)
+                              { c->publishCleanupConfig(); });
     }
 
     void onMessage(char* topic, char* payload, AsyncMqttClientMessageProperties properties, size_t len, size_t index, size_t total) {
         char msg[len + 1];
         memcpy(msg, payload, len);
         msg[len] = 0;
-        for (Ha::Button* cmd : buttons) {
-            if (String{ cmd->commandTopic }.equals(topic) && cmd->f != nullptr) {
-                cmd->f(msg);
-                return;
-            }
-        }
-        for (Ha::Switch* cmd : switches) {
-            if (String{ cmd->commandTopic }.equals(topic)) {
-                cmd->onCommand(msg);
-                return;
-            }
-        }
+        Command* cmd = Command::mapCommands[string{ topic }];
+        if (cmd) cmd->onCommand(msg);
     }
 
     void setup() {
diff --git a/gateway/include/utils.h b/gateway/include/utils.h
index 0c0bbe5..b7d4076 100644
--- a/gateway/include/utils.h
+++ b/gateway/include/utils.h
@@ -17,4 +17,10 @@ struct List {
         last = c;
     }
 
+    static void exec(List list, void(*f)(T*)) {
+        for (List::Container *c = list.first; c; c = c->next) {
+            f(c->t);
+        }
+    }
+
 };