diff --git a/src/ha.h b/src/ha.h
index df756bc..8465741 100644
--- a/src/ha.h
+++ b/src/ha.h
@@ -12,7 +12,9 @@ namespace Ha {
     uint16_t(*publisher)(const char* topic, const char* message);
     typedef void (*onMessage)(const char* msg);
 
+    struct Component;
     struct DeviceConfig {
+        friend struct Component;
         const char* id = nullptr;
         const char* name = nullptr;
         const char* model = nullptr;
@@ -24,17 +26,6 @@ namespace Ha {
             return *(new DeviceConfig{ id });
         }
 
-        void buildConfig(JsonDocument& jsonDoc) {
-            JsonObject device = jsonDoc.createNestedObject("device");
-            if (name) device["name"] = name;
-            if (model) device["model"] = model;
-            if (manufacturer) device["manufacturer"] = manufacturer;
-            if (area) device["suggested_area"] = area;
-            if (parent) device["via_device"] = parent->id;
-            JsonArray identifiers = device.createNestedArray("identifiers");
-            identifiers.add(id);
-        }
-
         DeviceConfig& withName(const char* value) {
             name = value;
             return *this;
@@ -62,6 +53,17 @@ namespace Ha {
 
     protected:
         DeviceConfig(const char* id) : id(id) {}
+
+        void buildConfig(JsonDocument& jsonDoc) {
+            JsonObject device = jsonDoc.createNestedObject("device");
+            if (name) device["name"] = name;
+            if (model) device["model"] = model;
+            if (manufacturer) device["manufacturer"] = manufacturer;
+            if (area) device["suggested_area"] = area;
+            if (parent) device["via_device"] = parent->id;
+            JsonArray identifiers = device.createNestedArray("identifiers");
+            identifiers.add(id);
+        }
     };
 
     struct Component {
@@ -99,6 +101,21 @@ namespace Ha {
             components.add(this);
         }
 
+        void publishConfig() {
+            StaticJsonDocument<JSON_SIZE> jsonDoc;
+            buildConfig(jsonDoc);
+
+            char message[JSON_SIZE];
+            serializeJson(jsonDoc, message);
+
+            publisher(configTopic, message);
+        }
+
+        void publishCleanupConfig() {
+            publisher(configTopic, "");
+        }
+
+    protected:
         virtual void buildUniqueId(char* uniqueId) {
             sprintf(uniqueId, "%s_%s", MAIN_DEVICE_ID, id);
         }
@@ -125,33 +142,20 @@ namespace Ha {
             jsonNumbers.addToJson(jsonDoc);
             jsonStrings.addToJson(jsonDoc);
         }
-
-        void publishConfig() {
-            StaticJsonDocument<JSON_SIZE> jsonDoc;
-            buildConfig(jsonDoc);
-
-            char message[JSON_SIZE];
-            serializeJson(jsonDoc, message);
-
-            publisher(configTopic, message);
-        }
-
-        void publishCleanupConfig() {
-            publisher(configTopic, "");
-        }
     };
 
     struct AbstractBuilder {
         static List<AbstractBuilder> builders;
 
-        AbstractBuilder() {
-            builders.add(this);
-        }
-
         static void deleteAll() {
             builders.forEach([](AbstractBuilder* builder) { delete builder; });
             builders.empty();
         }
+
+    protected:
+        AbstractBuilder() {
+            builders.add(this);
+        }
     };
 
     template <class T>
@@ -255,8 +259,6 @@ namespace Ha {
 
     struct Command : Component {
         bool retain = false;
-        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) {
@@ -268,6 +270,9 @@ namespace Ha {
             if (f) f(msg);
         }
 
+    protected:
+        char commandTopic[TOPIC_SIZE];
+        onMessage f;
         virtual void buildCommandConfig(JsonDocument& jsonDoc) = 0;
 
         void buildComponentConfig(JsonDocument& jsonDoc) override {
@@ -275,21 +280,19 @@ namespace Ha {
             if (retain) jsonDoc["retain"] = true;
             buildCommandConfig(jsonDoc);
         }
-
     };
 
     struct Button : Command {
 
         Button(const char* name, const char* id, onMessage f = nullptr) : Command(name, id, "button", f) {}
 
+    protected:
         void buildCommandConfig(JsonDocument& jsonDoc) override {}
 
     };
 
     struct StateConfig {
-        char stateTopic[TOPIC_SIZE];
         static unordered_map<string, Command*> mapStateTopics;
-        Component* cmp;
 
         StateConfig(Component* cmp) : cmp(cmp) {}
 
@@ -297,23 +300,22 @@ namespace Ha {
             sprintf(stateTopic, "homeassistant/%s/%s/%s/state", cmp->type, MAIN_DEVICE_ID, cmp->id);
         }
 
-        void buildConfig(JsonDocument& jsonDoc) {
-            if (stateTopic[0]) jsonDoc["state_topic"] = stateTopic;
-        }
-
         void updateState(const char* message) {
             if (stateTopic[0]) publisher(stateTopic, message);
         }
+
+    protected:
+        char stateTopic[TOPIC_SIZE];
+        Component* cmp;
+        void buildConfig(JsonDocument& jsonDoc) {
+            if (stateTopic[0]) jsonDoc["state_topic"] = stateTopic;
+        }
     };
 
     struct Switch : Command, StateConfig {
 
         Switch(const char* name, const char* id, onMessage f = nullptr) : Command(name, id, "switch", f), StateConfig(this) {}
 
-        void buildCommandConfig(JsonDocument& jsonDoc) override {
-            StateConfig::buildConfig(jsonDoc);
-        }
-
         void updateState(bool state) {
             StateConfig::updateState(state ? "ON" : "OFF");
         }
@@ -321,6 +323,11 @@ namespace Ha {
         void restoreFromState() {
             mapStateTopics.insert({stateTopic, this});
         }
+
+    protected:
+        void buildCommandConfig(JsonDocument& jsonDoc) override {
+            StateConfig::buildConfig(jsonDoc);
+        }
     };
 
     struct Number : Command, StateConfig {
@@ -329,13 +336,6 @@ namespace Ha {
         Number(const char* name, const char* id, unsigned int min, unsigned int max, unsigned int step, onMessage f)
             : Command(name, id, "number", f), StateConfig(this), min(min), max(max), step(step) {}
 
-        void buildCommandConfig(JsonDocument& jsonDoc) override {
-            StateConfig::buildConfig(jsonDoc);
-            jsonDoc["min"] = min;
-            jsonDoc["max"] = max;
-            jsonDoc["step"] = step;
-        }
-
         void updateState(unsigned int value) {
             char message[32];
             sprintf(message, "%u", value);
@@ -346,6 +346,13 @@ namespace Ha {
             mapStateTopics.insert({stateTopic, this});
         }
 
+    protected:
+        void buildCommandConfig(JsonDocument& jsonDoc) override {
+            StateConfig::buildConfig(jsonDoc);
+            jsonDoc["min"] = min;
+            jsonDoc["max"] = max;
+            jsonDoc["step"] = step;
+        }
     };
 
     struct Sensor : Component, StateConfig {
@@ -359,6 +366,7 @@ namespace Ha {
             mapSensors.insert({ id, this });
         }
 
+    protected:
         void buildUniqueId(char* uniqueId) override {
             if (multiValueComponent && deviceClass) {
                 sprintf(uniqueId, "%s_%s_%s", MAIN_DEVICE_ID, deviceClass, id);