diff --git a/platformio.ini b/platformio.ini
index a071319..475b250 100644
--- a/platformio.ini
+++ b/platformio.ini
@@ -63,7 +63,7 @@ lib_deps =
   mathieucarbou/AsyncTCP @ 3.2.14
   ; https://github.com/mathieucarbou/AsyncTCPSock/archive/refs/tags/v1.0.3-dev.zip
   mathieucarbou/ESPAsyncWebServer @ 3.3.22
-  mathieucarbou/MycilaConfig @ 6.0.4
+  mathieucarbou/MycilaConfig @ 7.0.3
   mathieucarbou/MycilaDS18 @ 4.1.1
   mathieucarbou/MycilaESPConnect @ 7.0.0
   mathieucarbou/MycilaEasyDisplay @ 3.0.2
diff --git a/src/Website.cpp b/src/Website.cpp
index 8b000cb..f3a0d73 100644
--- a/src/Website.cpp
+++ b/src/Website.cpp
@@ -4,8 +4,8 @@
  */
 #include <YaSolRWebsite.h>
 
-#include <unordered_map>
 #include <string>
+#include <unordered_map>
 
 #define HIDDEN_PWD "********"
 
@@ -55,8 +55,8 @@ void YaSolR::WebsiteClass::initLayout() {
     config.set(KEY_OUTPUT2_DIMMER_LIMIT, "100", false);
 
     router.beginCalibration([]() {
-      config.set(KEY_OUTPUT1_RESISTANCE, Mycila::string::to_string(router.getOutputs()[0]->config.calibratedResistance, 2).c_str());
-      config.set(KEY_OUTPUT2_RESISTANCE, Mycila::string::to_string(router.getOutputs()[1]->config.calibratedResistance, 2).c_str());
+      config.set(KEY_OUTPUT1_RESISTANCE, Mycila::string::to_string(router.getOutputs()[0]->config.calibratedResistance, 2));
+      config.set(KEY_OUTPUT2_RESISTANCE, Mycila::string::to_string(router.getOutputs()[1]->config.calibratedResistance, 2));
     });
 
     YaSolR::Website.initCards();
@@ -393,7 +393,7 @@ void YaSolR::WebsiteClass::initLayout() {
   _output1DimmerMapper.attachCallback([this](const char* value) {
     const char* comma = strchr(value, ',');
     if (comma != nullptr) {
-      config.set(KEY_OUTPUT1_DIMMER_MIN, std::string(value, comma - value).c_str());
+      config.set(KEY_OUTPUT1_DIMMER_MIN, std::string(value, comma - value));
       config.set(KEY_OUTPUT1_DIMMER_MAX, comma + 1);
     }
     _output1DimmerMapper.update(value);
@@ -402,7 +402,7 @@ void YaSolR::WebsiteClass::initLayout() {
   _output2DimmerMapper.attachCallback([this](const char* value) {
     const char* comma = strchr(value, ',');
     if (comma != nullptr) {
-      config.set(KEY_OUTPUT2_DIMMER_MIN, std::string(value, comma - value).c_str());
+      config.set(KEY_OUTPUT2_DIMMER_MIN, std::string(value, comma - value));
       config.set(KEY_OUTPUT2_DIMMER_MAX, comma + 1);
     }
     _output2DimmerMapper.update(value);
@@ -671,7 +671,7 @@ void YaSolR::WebsiteClass::initCards() {
 
   _displayType.update(config.get(KEY_DISPLAY_TYPE), "SH1106,SH1107,SSD1306");
   _displaySpeed.update(config.getInt(KEY_DISPLAY_SPEED));
-  _displayRotation.update((std::string(config.get(KEY_DISPLAY_ROTATION)) + "°").c_str(), "0°,90°,180°,270°");
+  _displayRotation.update((config.getString(KEY_DISPLAY_ROTATION) + "°").c_str(), "0°,90°,180°,270°");
   _output1RelayType.update(config.get(KEY_OUTPUT1_RELAY_TYPE), "NO,NC");
   _output2RelayType.update(config.get(KEY_OUTPUT2_RELAY_TYPE), "NO,NC");
   _relay1Type.update(config.get(KEY_RELAY1_TYPE), "NO,NC");
@@ -680,8 +680,8 @@ void YaSolR::WebsiteClass::initCards() {
   _relay2Load.update(load2);
   _output1ResistanceInput.update(config.get(KEY_OUTPUT1_RESISTANCE), config.getFloat(KEY_OUTPUT1_RESISTANCE) == 0 ? DASH_STATUS_DANGER : DASH_STATUS_SUCCESS);
   _output2ResistanceInput.update(config.get(KEY_OUTPUT2_RESISTANCE), config.getFloat(KEY_OUTPUT2_RESISTANCE) == 0 ? DASH_STATUS_DANGER : DASH_STATUS_SUCCESS);
-  _output1DimmerMapper.update((std::string(config.get(KEY_OUTPUT1_DIMMER_MIN)) + "," + config.get(KEY_OUTPUT1_DIMMER_MAX)).c_str());
-  _output2DimmerMapper.update((std::string(config.get(KEY_OUTPUT2_DIMMER_MIN)) + "," + config.get(KEY_OUTPUT2_DIMMER_MAX)).c_str());
+  _output1DimmerMapper.update((config.getString(KEY_OUTPUT1_DIMMER_MIN) + "," + config.get(KEY_OUTPUT1_DIMMER_MAX)).c_str());
+  _output2DimmerMapper.update((config.getString(KEY_OUTPUT2_DIMMER_MIN) + "," + config.get(KEY_OUTPUT2_DIMMER_MAX)).c_str());
 
   _displayType.setDisplay(config.getBool(KEY_ENABLE_DISPLAY));
   _displaySpeed.setDisplay(config.getBool(KEY_ENABLE_DISPLAY));
@@ -991,7 +991,7 @@ void YaSolR::WebsiteClass::resetPID() {
 
 void YaSolR::WebsiteClass::_sliderConfig(Card& card, const char* key) {
   card.attachCallback([key, &card](int value) {
-    config.set(key, std::to_string(value).c_str());
+    config.set(key, std::to_string(value));
     card.update(config.getInt(key));
     dashboard.refreshCard(&card);
   });
@@ -999,7 +999,7 @@ void YaSolR::WebsiteClass::_sliderConfig(Card& card, const char* key) {
 
 void YaSolR::WebsiteClass::_percentageSlider(Card& card, const char* key) {
   card.attachCallback([key, &card](int value) {
-    config.set(key, std::to_string(value).c_str());
+    config.set(key, std::to_string(value));
     card.update(value);
     dashboard.refreshCard(&card);
   });
@@ -1023,7 +1023,7 @@ void YaSolR::WebsiteClass::_numConfig(Card& card, const char* key) {
 #ifdef APP_MODEL_PRO
   card.attachCallback([key, &card](const char* value) {
     if (value[0]) {
-      config.set(key, std::to_string(strtol(value, nullptr, 10)).c_str());
+      config.set(key, std::to_string(strtol(value, nullptr, 10)));
     } else {
       config.unset(key);
     }
@@ -1037,7 +1037,7 @@ void YaSolR::WebsiteClass::_pinConfig(Card& card, const char* key) {
 #ifdef APP_MODEL_PRO
   card.attachCallback([key, &card, this](const char* value) {
     if (value[0]) {
-      config.set(key, std::to_string(strtol(value, nullptr, 10)).c_str());
+      config.set(key, std::to_string(strtol(value, nullptr, 10)));
     } else {
       config.unset(key);
     }
diff --git a/src/init/Boot.cpp b/src/init/Boot.cpp
index 63d4023..51a427c 100644
--- a/src/init/Boot.cpp
+++ b/src/init/Boot.cpp
@@ -66,7 +66,7 @@ Mycila::Task bootTask("Boot", [](void* params) {
   config.configure(KEY_MQTT_PUBLISH_INTERVAL, "5");
   config.configure(KEY_MQTT_SECURED, YASOLR_FALSE);
   config.configure(KEY_MQTT_SERVER);
-  config.configure(KEY_MQTT_TOPIC, Mycila::AppInfo.defaultMqttClientId.c_str());
+  config.configure(KEY_MQTT_TOPIC, Mycila::AppInfo.defaultMqttClientId);
   config.configure(KEY_MQTT_USERNAME);
   config.configure(KEY_NET_DNS);
   config.configure(KEY_NET_GATEWAY);
@@ -109,30 +109,30 @@ Mycila::Task bootTask("Boot", [](void* params) {
   config.configure(KEY_PID_OUT_MIN, "-1000");
   config.configure(KEY_PID_P_MODE, "2");
   config.configure(KEY_PID_SETPOINT, "0");
-  config.configure(KEY_PIN_DISPLAY_SCL, std::to_string(YASOLR_DISPLAY_CLOCK_PIN).c_str());
-  config.configure(KEY_PIN_DISPLAY_SDA, std::to_string(YASOLR_DISPLAY_DATA_PIN).c_str());
-  config.configure(KEY_PIN_JSY_RX, std::to_string(YASOLR_JSY_RX_PIN).c_str());
-  config.configure(KEY_PIN_JSY_TX, std::to_string(YASOLR_JSY_TX_PIN).c_str());
-  config.configure(KEY_PIN_LIGHTS_GREEN, std::to_string(YASOLR_LIGHTS_GREEN_PIN).c_str());
-  config.configure(KEY_PIN_LIGHTS_RED, std::to_string(YASOLR_LIGHTS_RED_PIN).c_str());
-  config.configure(KEY_PIN_LIGHTS_YELLOW, std::to_string(YASOLR_LIGHTS_YELLOW_PIN).c_str());
-  config.configure(KEY_PIN_OUTPUT1_DIMMER, std::to_string(YASOLR_OUTPUT1_DIMMER_PIN).c_str());
-  config.configure(KEY_PIN_OUTPUT1_DS18, std::to_string(YASOLR_OUTPUT1_TEMP_PIN).c_str());
-  config.configure(KEY_PIN_OUTPUT1_RELAY, std::to_string(YASOLR_OUTPUT1_RELAY_PIN).c_str());
-  config.configure(KEY_PIN_OUTPUT2_DIMMER, std::to_string(YASOLR_OUTPUT2_DIMMER_PIN).c_str());
-  config.configure(KEY_PIN_OUTPUT2_DS18, std::to_string(YASOLR_OUTPUT2_TEMP_PIN).c_str());
-  config.configure(KEY_PIN_OUTPUT2_RELAY, std::to_string(YASOLR_OUTPUT2_RELAY_PIN).c_str());
-  config.configure(KEY_PIN_PZEM_RX, std::to_string(YASOLR_PZEM_RX_PIN).c_str());
-  config.configure(KEY_PIN_PZEM_TX, std::to_string(YASOLR_PZEM_TX_PIN).c_str());
-  config.configure(KEY_PIN_RELAY1, std::to_string(YASOLR_RELAY1_PIN).c_str());
-  config.configure(KEY_PIN_RELAY2, std::to_string(YASOLR_RELAY2_PIN).c_str());
-  config.configure(KEY_PIN_ROUTER_DS18, std::to_string(YASOLR_SYSTEM_TEMP_PIN).c_str());
-  config.configure(KEY_PIN_ZCD, std::to_string(YASOLR_ZCD_PIN).c_str());
+  config.configure(KEY_PIN_DISPLAY_SCL, std::to_string(YASOLR_DISPLAY_CLOCK_PIN));
+  config.configure(KEY_PIN_DISPLAY_SDA, std::to_string(YASOLR_DISPLAY_DATA_PIN));
+  config.configure(KEY_PIN_JSY_RX, std::to_string(YASOLR_JSY_RX_PIN));
+  config.configure(KEY_PIN_JSY_TX, std::to_string(YASOLR_JSY_TX_PIN));
+  config.configure(KEY_PIN_LIGHTS_GREEN, std::to_string(YASOLR_LIGHTS_GREEN_PIN));
+  config.configure(KEY_PIN_LIGHTS_RED, std::to_string(YASOLR_LIGHTS_RED_PIN));
+  config.configure(KEY_PIN_LIGHTS_YELLOW, std::to_string(YASOLR_LIGHTS_YELLOW_PIN));
+  config.configure(KEY_PIN_OUTPUT1_DIMMER, std::to_string(YASOLR_OUTPUT1_DIMMER_PIN));
+  config.configure(KEY_PIN_OUTPUT1_DS18, std::to_string(YASOLR_OUTPUT1_TEMP_PIN));
+  config.configure(KEY_PIN_OUTPUT1_RELAY, std::to_string(YASOLR_OUTPUT1_RELAY_PIN));
+  config.configure(KEY_PIN_OUTPUT2_DIMMER, std::to_string(YASOLR_OUTPUT2_DIMMER_PIN));
+  config.configure(KEY_PIN_OUTPUT2_DS18, std::to_string(YASOLR_OUTPUT2_TEMP_PIN));
+  config.configure(KEY_PIN_OUTPUT2_RELAY, std::to_string(YASOLR_OUTPUT2_RELAY_PIN));
+  config.configure(KEY_PIN_PZEM_RX, std::to_string(YASOLR_PZEM_RX_PIN));
+  config.configure(KEY_PIN_PZEM_TX, std::to_string(YASOLR_PZEM_TX_PIN));
+  config.configure(KEY_PIN_RELAY1, std::to_string(YASOLR_RELAY1_PIN));
+  config.configure(KEY_PIN_RELAY2, std::to_string(YASOLR_RELAY2_PIN));
+  config.configure(KEY_PIN_ROUTER_DS18, std::to_string(YASOLR_SYSTEM_TEMP_PIN));
+  config.configure(KEY_PIN_ZCD, std::to_string(YASOLR_ZCD_PIN));
   config.configure(KEY_RELAY1_LOAD, "0");
   config.configure(KEY_RELAY1_TYPE, YASOLR_RELAY_TYPE_NO);
   config.configure(KEY_RELAY2_LOAD, "0");
   config.configure(KEY_RELAY2_TYPE, YASOLR_RELAY_TYPE_NO);
-  config.configure(KEY_UDP_PORT, std::to_string(YASOLR_UDP_PORT).c_str());
+  config.configure(KEY_UDP_PORT, std::to_string(YASOLR_UDP_PORT));
   config.configure(KEY_WIFI_PASSWORD);
   config.configure(KEY_WIFI_SSID);
 
diff --git a/src/init/Config.cpp b/src/init/Config.cpp
index dc7cff0..57c8a7a 100644
--- a/src/init/Config.cpp
+++ b/src/init/Config.cpp
@@ -107,11 +107,11 @@ Mycila::Task initConfigTask("Init Config", [](void* params) {
   haDiscovery.setDiscoveryTopic(config.get(KEY_HA_DISCOVERY_TOPIC));
   haDiscovery.setWillTopic((std::string(config.get(KEY_MQTT_TOPIC)) + YASOLR_MQTT_WILL_TOPIC).c_str());
   haDiscovery.begin({
-                      .id = Mycila::AppInfo.defaultMqttClientId.c_str(),
-                      .name = Mycila::AppInfo.defaultSSID.c_str(),
-                      .version = Mycila::AppInfo.version.c_str(),
-                      .model = (Mycila::AppInfo.name + " " + Mycila::AppInfo.model).c_str(),
-                      .manufacturer = Mycila::AppInfo.manufacturer.c_str(),
+                      .id = Mycila::AppInfo.defaultMqttClientId,
+                      .name = Mycila::AppInfo.defaultSSID,
+                      .version = Mycila::AppInfo.version,
+                      .model = Mycila::AppInfo.name + " " + Mycila::AppInfo.model,
+                      .manufacturer = Mycila::AppInfo.manufacturer,
                       .url = std::string("http://") + espConnect.getIPAddress().toString().c_str(),
                     },
                     config.get(KEY_MQTT_TOPIC),
@@ -157,7 +157,7 @@ Mycila::Task initConfigTask("Init Config", [](void* params) {
 
   // Display
   if (config.getBool(KEY_ENABLE_DISPLAY)) {
-    const std::string displayType = config.get(KEY_DISPLAY_TYPE);
+    const std::string& displayType = config.getString(KEY_DISPLAY_TYPE);
     if (displayType == "SSD1306")
       display.begin(Mycila::EasyDisplayType::SSD1306, config.getLong(KEY_PIN_DISPLAY_SCL), config.getLong(KEY_PIN_DISPLAY_SDA), config.getLong(KEY_DISPLAY_ROTATION));
     else if (displayType == "SH1107")
diff --git a/src/init/Events.cpp b/src/init/Events.cpp
index b8f14e5..57dab39 100644
--- a/src/init/Events.cpp
+++ b/src/init/Events.cpp
@@ -23,8 +23,8 @@ Mycila::Task initEventsTask("Init Events", [](void* params) {
     restartTask.resume();
   });
 
-  config.listen([](const char* k, const char* newValue) {
-    logger.info(TAG, "'%s' => '%s'", k, newValue);
+  config.listen([](const char* k, const std::string& newValue) {
+    logger.info(TAG, "'%s' => '%s'", k, newValue.c_str());
     const std::string key = k;
 
     if (key == KEY_ENABLE_DEBUG) {
@@ -199,7 +199,7 @@ Mycila::Task initEventsTask("Init Events", [](void* params) {
     } else if (key == KEY_ENABLE_DISPLAY) {
       display.end();
       if (config.getBool(KEY_ENABLE_DISPLAY)) {
-        const std::string displayType = config.get(KEY_DISPLAY_TYPE);
+        const std::string& displayType = config.getString(KEY_DISPLAY_TYPE);
         if (displayType == "SSD1306")
           display.begin(Mycila::EasyDisplayType::SSD1306, config.getLong(KEY_PIN_DISPLAY_SCL), config.getLong(KEY_PIN_DISPLAY_SDA), config.getLong(KEY_DISPLAY_ROTATION));
         else if (displayType == "SH1107")
@@ -274,8 +274,8 @@ Mycila::Task initEventsTask("Init Events", [](void* params) {
         } else {
           logger.info(TAG, "Captive Portal: WiFi configured");
           config.setBool(KEY_ENABLE_AP_MODE, false);
-          config.set(KEY_WIFI_SSID, espConnect.getConfiguredWiFiSSID().c_str());
-          config.set(KEY_WIFI_PASSWORD, espConnect.getConfiguredWiFiPassword().c_str());
+          config.set(KEY_WIFI_SSID, espConnect.getConfiguredWiFiSSID());
+          config.set(KEY_WIFI_PASSWORD, espConnect.getConfiguredWiFiPassword());
         }
         break;
       }
diff --git a/src/init/MQTT.cpp b/src/init/MQTT.cpp
index 70ce3f2..1f5696f 100644
--- a/src/init/MQTT.cpp
+++ b/src/init/MQTT.cpp
@@ -9,7 +9,7 @@
 Mycila::Task initMqttSubscribersTask("Init MQTT Subscribers", [](void* params) {
   logger.info(TAG, "Initializing MQTT Subscribers");
 
-  const std::string baseTopic = config.get(KEY_MQTT_TOPIC);
+  const std::string& baseTopic = config.getString(KEY_MQTT_TOPIC);
 
   // config
 
@@ -20,7 +20,7 @@ Mycila::Task initMqttSubscribersTask("Init MQTT Subscribers", [](void* params) {
     const std::size_t start = topic.rfind("/", end - 1);
     const char* key = config.keyRef(topic.substr(start + 1, end - start - 1).c_str());
     if (key)
-      config.set(key, payload.c_str());
+      config.set(key, payload);
   });
 
   // relays
diff --git a/src/tasks/MQTT.cpp b/src/tasks/MQTT.cpp
index 0478597..8ec4c7b 100644
--- a/src/tasks/MQTT.cpp
+++ b/src/tasks/MQTT.cpp
@@ -15,13 +15,13 @@ Mycila::Task mqttConfigTask("MQTT Config", Mycila::TaskType::ONCE, [](void* para
     bool secured = config.getBool(KEY_MQTT_SECURED);
 
     Mycila::MQTT::Config mqttConfig;
-    mqttConfig.server = config.get(KEY_MQTT_SERVER);
+    mqttConfig.server = config.getString(KEY_MQTT_SERVER);
     mqttConfig.port = static_cast<uint16_t>(config.getLong(KEY_MQTT_PORT));
     mqttConfig.secured = secured;
-    mqttConfig.username = config.get(KEY_MQTT_USERNAME);
-    mqttConfig.password = config.get(KEY_MQTT_PASSWORD);
-    mqttConfig.clientId = Mycila::AppInfo.defaultMqttClientId.c_str();
-    mqttConfig.willTopic = std::string(config.get(KEY_MQTT_TOPIC)) + YASOLR_MQTT_WILL_TOPIC;
+    mqttConfig.username = config.getString(KEY_MQTT_USERNAME);
+    mqttConfig.password = config.getString(KEY_MQTT_PASSWORD);
+    mqttConfig.clientId = Mycila::AppInfo.defaultMqttClientId;
+    mqttConfig.willTopic = config.getString(KEY_MQTT_TOPIC) + YASOLR_MQTT_WILL_TOPIC;
     mqttConfig.keepAlive = YASOLR_MQTT_KEEPALIVE;
 
     if (secured) {
@@ -48,7 +48,7 @@ Mycila::Task mqttConfigTask("MQTT Config", Mycila::TaskType::ONCE, [](void* para
 
 Mycila::Task mqttPublishStaticTask("MQTT Static", Mycila::TaskType::ONCE, [](void* params) {
   logger.debug(TAG, "Publishing static data to MQTT");
-  const std::string baseTopic = config.get(KEY_MQTT_TOPIC);
+  const std::string& baseTopic = config.getString(KEY_MQTT_TOPIC);
 
   mqtt.publish((baseTopic + "/system/app/manufacturer").c_str(), Mycila::AppInfo.manufacturer.c_str(), true);
   mqtt.publish((baseTopic + "/system/app/model").c_str(), Mycila::AppInfo.model.c_str(), true);
@@ -79,7 +79,7 @@ Mycila::Task mqttPublishStaticTask("MQTT Static", Mycila::TaskType::ONCE, [](voi
 
 Mycila::Task mqttPublishConfigTask("MQTT Config", Mycila::TaskType::ONCE, [](void* params) {
   logger.debug(TAG, "Publishing config to MQTT");
-  const std::string baseTopic = config.get(KEY_MQTT_TOPIC);
+  const std::string& baseTopic = config.getString(KEY_MQTT_TOPIC);
 
   for (auto& key : config.keys()) {
     const char* value = config.get(key);
@@ -90,7 +90,7 @@ Mycila::Task mqttPublishConfigTask("MQTT Config", Mycila::TaskType::ONCE, [](voi
 });
 
 Mycila::Task mqttPublishTask("MQTT", [](void* params) {
-  const std::string baseTopic = config.get(KEY_MQTT_TOPIC);
+  const std::string& baseTopic = config.getString(KEY_MQTT_TOPIC);
 
   Mycila::System::Memory memory;
   Mycila::System::getMemory(memory);