diff --git a/.github/workflows/mqtt_cxx__build.yml b/.github/workflows/mqtt_cxx__build.yml
index e99111c8dd..238df69662 100644
--- a/.github/workflows/mqtt_cxx__build.yml
+++ b/.github/workflows/mqtt_cxx__build.yml
@@ -13,9 +13,9 @@ jobs:
     name: Build
     strategy:
       matrix:
-        idf_ver: ["latest", "release-v5.0", "release-v5.1", "release-v5.2", "release-v5.3"]
+        idf_ver: ["release-v5.1", "release-v5.2", "release-v5.3", "release-v5.4", "release-v5.5"]
         idf_target: ["esp32"]
-        test: [ { app: mqtt-basic, path: "components/esp_mqtt_cxx/examples" }]
+        test: [ { app: mqtt-basic, path: "components/esp_mqtt_cxx/examples" }, { app: test, path: "components/esp_mqtt_cxx/test/unit" }]
     runs-on: ubuntu-22.04
     container: espressif/idf:${{ matrix.idf_ver }}
     steps:
@@ -25,8 +25,7 @@ jobs:
           submodules: recursive
       - name: Build ${{ matrix.test.app }} with IDF-${{ matrix.idf_ver }} for ${{ matrix.idf_target }}
         shell: bash
-        working-directory: ${{matrix.test.path}}
         run: |
           . ${IDF_PATH}/export.sh
           pip install idf-component-manager idf-build-apps --upgrade
-          python ../../../ci/build_apps.py ./${{ matrix.test.app }} --target ${{ matrix.idf_target }} -vv --preserve-all --pytest-app
+          python ./ci/build_apps.py ./${{ matrix.test.path }} --target ${{ matrix.idf_target }} -vv --preserve-all -c
diff --git a/components/esp_mqtt_cxx/.cz.yaml b/components/esp_mqtt_cxx/.cz.yaml
index f8ce49be5c..32e1cab2c2 100644
--- a/components/esp_mqtt_cxx/.cz.yaml
+++ b/components/esp_mqtt_cxx/.cz.yaml
@@ -3,6 +3,6 @@ commitizen:
   bump_message: 'bump(mqtt_cxx): $current_version -> $new_version'
   pre_bump_hooks: python ../../ci/changelog.py esp_mqtt_cxx
   tag_format: mqtt_cxx-v$version
-  version: 0.4.0
+  version: 0.5.0
   version_files:
   - idf_component.yml
diff --git a/components/esp_mqtt_cxx/CHANGELOG.md b/components/esp_mqtt_cxx/CHANGELOG.md
index a39fd7050c..8b14097e23 100644
--- a/components/esp_mqtt_cxx/CHANGELOG.md
+++ b/components/esp_mqtt_cxx/CHANGELOG.md
@@ -1,5 +1,13 @@
 # Changelog
 
+## [0.5.0](https://github.com/espressif/esp-protocols/commits/mqtt_cxx-v0.5.0)
+
+### Bug Fixes
+
+- Implement simple unit tests ([f41c4a0a](https://github.com/espressif/esp-protocols/commit/f41c4a0a))
+- Fix to construct in two steps ([d979e1b3](https://github.com/espressif/esp-protocols/commit/d979e1b3), [#631](https://github.com/espressif/esp-protocols/issues/631))
+- Add explicit dependency on esp-mqtt if needed ([3d5e11b8](https://github.com/espressif/esp-protocols/commit/3d5e11b8))
+
 ## [0.4.0](https://github.com/espressif/esp-protocols/commits/mqtt_cxx-v0.4.0)
 
 ### Bug Fixes
diff --git a/components/esp_mqtt_cxx/esp_mqtt_cxx.cpp b/components/esp_mqtt_cxx/esp_mqtt_cxx.cpp
index 75c8d6db09..9e077719f2 100644
--- a/components/esp_mqtt_cxx/esp_mqtt_cxx.cpp
+++ b/components/esp_mqtt_cxx/esp_mqtt_cxx.cpp
@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2021-2024 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2021-2025 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -163,7 +163,20 @@ Client::Client(esp_mqtt_client_config_t const &config) :  handler(esp_mqtt_clien
         throw MQTTException(ESP_FAIL);
     };
     CHECK_THROW_SPECIFIC(esp_mqtt_client_register_event(handler.get(), MQTT_EVENT_ANY, mqtt_event_handler, this), mqtt::MQTTException);
+}
+
+void Client::start()
+{
+    if (started) {
+        return;
+    }
     CHECK_THROW_SPECIFIC(esp_mqtt_client_start(handler.get()), mqtt::MQTTException);
+    started = true;
+}
+
+bool Client::is_started() const noexcept
+{
+    return started;
 }
 
 void Client::mqtt_event_handler(void *handler_args, esp_event_base_t base, int32_t event_id, void *event_data) noexcept
diff --git a/components/esp_mqtt_cxx/examples/ssl/main/mqtt_ssl_example.cpp b/components/esp_mqtt_cxx/examples/ssl/main/mqtt_ssl_example.cpp
index 3bdf35640d..1651a3f65a 100644
--- a/components/esp_mqtt_cxx/examples/ssl/main/mqtt_ssl_example.cpp
+++ b/components/esp_mqtt_cxx/examples/ssl/main/mqtt_ssl_example.cpp
@@ -83,8 +83,9 @@ extern "C" void app_main(void)
     idf::mqtt::Configuration config{};
 
     MyClient client{broker, credentials, config};
+    client.start();
     while (true) {
         constexpr TickType_t xDelay = 500 / portTICK_PERIOD_MS;
-        vTaskDelay( xDelay );
+        vTaskDelay(xDelay);
     }
 }
diff --git a/components/esp_mqtt_cxx/examples/tcp/main/mqtt_tcp_example.cpp b/components/esp_mqtt_cxx/examples/tcp/main/mqtt_tcp_example.cpp
index 67517d246d..fcd0e1bcaf 100644
--- a/components/esp_mqtt_cxx/examples/tcp/main/mqtt_tcp_example.cpp
+++ b/components/esp_mqtt_cxx/examples/tcp/main/mqtt_tcp_example.cpp
@@ -78,6 +78,7 @@ extern "C" void app_main(void)
     mqtt::Configuration config{};
 
     MyClient client{broker, credentials, config};
+    client.start();
 
     while (true) {
         constexpr TickType_t xDelay = 500 / portTICK_PERIOD_MS;
diff --git a/components/esp_mqtt_cxx/idf_component.yml b/components/esp_mqtt_cxx/idf_component.yml
index 904dd3fc7d..bc041f2cb0 100644
--- a/components/esp_mqtt_cxx/idf_component.yml
+++ b/components/esp_mqtt_cxx/idf_component.yml
@@ -1,4 +1,4 @@
-version: "0.4.0"
+version: "0.5.0"
 description: C++ APIs for ESP-MQTT library
 url: https://github.com/espressif/esp-protocols/tree/master/components/esp_mqtt_cxx
 issues: https://github.com/espressif/esp-protocols/issues
@@ -8,7 +8,7 @@ dependencies:
   espressif/esp-idf-cxx: "^1.0.0-beta"
   # Required IDF version
   idf:
-    version: ">=5.0"
+    version: ">=5.0,<6.0"
   espressif/mqtt:
     rules:
     - if: idf_version >=6.0
diff --git a/components/esp_mqtt_cxx/include/esp_mqtt.hpp b/components/esp_mqtt_cxx/include/esp_mqtt.hpp
index 4a5b9d286c..9f81ad7786 100644
--- a/components/esp_mqtt_cxx/include/esp_mqtt.hpp
+++ b/components/esp_mqtt_cxx/include/esp_mqtt.hpp
@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2021-2023 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2021-2025 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -165,6 +165,19 @@ class Client {
      */
     Client(const esp_mqtt_client_config_t &config);
 
+    /**
+     * @brief Start the underlying esp-mqtt client
+     *
+     * Must be called after the derived class has finished constructing to avoid
+     * events being dispatched to partially constructed objects.
+     */
+    void start();
+
+    /**
+     * @brief Check whether start() has been called
+     */
+    [[nodiscard]] bool is_started() const noexcept;
+
     /**
      * @brief Subscribe to topic
      *
@@ -245,13 +258,13 @@ class Client {
     */
     virtual void on_error(const esp_mqtt_event_handle_t event);
     /**
-    * @brief Called if there is an disconnection event
+    * @brief Called if there is a disconnection event
     *
     * @param event mqtt event data
     */
     virtual void on_disconnected(const esp_mqtt_event_handle_t event);
     /**
-    * @brief Called if there is an subscribed event
+    * @brief Called if there is a subscribed event
     *
     * @param event mqtt event data
     */
@@ -263,26 +276,26 @@ class Client {
     */
     virtual void on_unsubscribed(const esp_mqtt_event_handle_t event);
     /**
-    * @brief Called if there is an published event
+    * @brief Called if there is a published event
     *
     * @param event mqtt event data
     */
     virtual void on_published(const esp_mqtt_event_handle_t event);
     /**
-    * @brief Called if there is an before connect event
+    * @brief Called if there is a before connect event
     *
     * @param event mqtt event data
     */
     virtual void on_before_connect(const esp_mqtt_event_handle_t event);
     /**
-    * @brief Called if there is an connected event
+    * @brief Called if there is a connected event
     *
     * @param event mqtt event data
     *
     */
     virtual void on_connected(const esp_mqtt_event_handle_t event) = 0;
     /**
-    * @brief Called if there is an data event
+    * @brief Called if there is a data event
     *
     * @param event mqtt event data
     *
@@ -292,5 +305,6 @@ class Client {
     static void mqtt_event_handler(void *handler_args, esp_event_base_t base, int32_t event_id,
                                    void *event_data) noexcept;
     void init(const esp_mqtt_client_config_t &config);
+    bool started{false};
 };
 } // namespace idf::mqtt
diff --git a/components/esp_mqtt_cxx/test/unit/CMakeLists.txt b/components/esp_mqtt_cxx/test/unit/CMakeLists.txt
new file mode 100644
index 0000000000..f0596f7ec3
--- /dev/null
+++ b/components/esp_mqtt_cxx/test/unit/CMakeLists.txt
@@ -0,0 +1,10 @@
+cmake_minimum_required(VERSION 3.5)
+
+
+include($ENV{IDF_PATH}/tools/cmake/project.cmake)
+if(${IDF_TARGET} STREQUAL "linux")
+    set(EXTRA_COMPONENT_DIRS "../../../../common_components/linux_compat")
+    set(COMPONENTS main)
+endif()
+
+project(esp_mqtt_cxx_host_test)
diff --git a/components/esp_mqtt_cxx/test/unit/README.md b/components/esp_mqtt_cxx/test/unit/README.md
new file mode 100644
index 0000000000..166928d4d9
--- /dev/null
+++ b/components/esp_mqtt_cxx/test/unit/README.md
@@ -0,0 +1,24 @@
+# Test basic mqtt_cxx wrapper operations
+
+## Warning: Linux target not supported, this test works only on target
+
+## Example output
+```
+I (588) main_task: Started on CPU0
+I (598) main_task: Calling app_main()
+Randomness seeded to: 374196253
+I (608) mqtt_client_cpp: MQTT_EVENT_BEFORE_CONNECT
+E (618) esp-tls: [sock=54] delayed connect error: Connection reset by peer
+E (618) transport_base: Failed to open a new connection: 32772
+E (618) mqtt_client: Error transport connect
+I (618) mqtt_client_cpp: MQTT_EVENT_ERROR
+E (628) mqtt_client_cpp: Last error reported from esp-tls: 0x8004
+E (628) mqtt_client_cpp: Last error captured as transport's socket errno: 0x68
+I (638) mqtt_client_cpp: Last errno string (Connection reset by peer)
+I (648) mqtt_client_cpp: MQTT_EVENT_DISCONNECTED
+===============================================================================
+All tests passed (6 assertions in 1 test case)
+
+Test passed!
+I (5658) main_task: Returned from app_main()
+```
diff --git a/components/esp_mqtt_cxx/test/unit/main/CMakeLists.txt b/components/esp_mqtt_cxx/test/unit/main/CMakeLists.txt
new file mode 100644
index 0000000000..0c90f37ae6
--- /dev/null
+++ b/components/esp_mqtt_cxx/test/unit/main/CMakeLists.txt
@@ -0,0 +1,2 @@
+idf_component_register(SRCS "test_esp_mqtt_cxx.cpp"
+                        WHOLE_ARCHIVE)
diff --git a/components/esp_mqtt_cxx/test/unit/main/idf_component.yml b/components/esp_mqtt_cxx/test/unit/main/idf_component.yml
new file mode 100644
index 0000000000..6d27d03350
--- /dev/null
+++ b/components/esp_mqtt_cxx/test/unit/main/idf_component.yml
@@ -0,0 +1,5 @@
+dependencies:
+  espressif/catch2: "^3.4.0"
+  esp_mqtt_cxx:
+    version: "*"
+    override_path: '../../../'
diff --git a/components/esp_mqtt_cxx/test/unit/main/test_esp_mqtt_cxx.cpp b/components/esp_mqtt_cxx/test/unit/main/test_esp_mqtt_cxx.cpp
new file mode 100644
index 0000000000..d141724300
--- /dev/null
+++ b/components/esp_mqtt_cxx/test/unit/main/test_esp_mqtt_cxx.cpp
@@ -0,0 +1,92 @@
+/*
+ * SPDX-FileCopyrightText: 2025 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+#include "catch2/catch_session.hpp"
+#include "catch2/catch_test_macros.hpp"
+#include "esp_mqtt.hpp"
+#include "esp_mqtt_client_config.hpp"
+#include "esp_netif.h"
+
+namespace mqtt = idf::mqtt;
+
+namespace {
+class TestClient final : public mqtt::Client {
+public:
+    using mqtt::Client::Client;
+
+    bool constructed{false};
+    bool before_connect{false};
+    bool disconnected{false};
+
+    TestClient(const mqtt::BrokerConfiguration &broker, const mqtt::ClientCredentials &credentials, const mqtt::Configuration &config) :
+        mqtt::Client(broker, credentials, config)
+    {
+        constructed = true;
+    }
+
+private:
+    void on_connected(esp_mqtt_event_handle_t const event) override
+    {
+        CHECK(constructed);
+    }
+
+    void on_data(esp_mqtt_event_handle_t const event) override
+    {
+        CHECK(constructed);
+    }
+
+    void on_before_connect(esp_mqtt_event_handle_t const event) override
+    {
+        CHECK(constructed);
+        before_connect = true;
+    }
+
+    void on_disconnected(const esp_mqtt_event_handle_t event) override
+    {
+        CHECK(constructed);
+        disconnected = true;
+
+    }
+
+};
+} // namespace
+
+TEST_CASE("Client does not auto-start and can dispatch events after construction", "[esp_mqtt_cxx]")
+{
+    mqtt::BrokerConfiguration broker{
+        .address = mqtt::URI{std::string{"mqtt://127.0.0.1:1883"}},
+        .security = mqtt::Insecure{}
+    };
+    mqtt::ClientCredentials credentials{};
+    mqtt::Configuration config{};
+
+    TestClient client{broker, credentials, config};
+
+    REQUIRE(client.is_started() == false);
+
+    // start the client and expect disconnection (reset by peer)
+    // since no server's running on this ESP32
+    client.start();
+    CHECK(client.is_started() == true);
+
+    CHECK(client.before_connect);
+    usleep(10000);
+    CHECK(client.disconnected);
+}
+
+extern "C" void app_main(void)
+{
+    ESP_ERROR_CHECK(esp_netif_init());
+    ESP_ERROR_CHECK(esp_event_loop_create_default());
+
+    Catch::Session session;
+
+    int failures = session.run();
+    if (failures > 0) {
+        printf("TEST FAILED! number of failures=%d\n", failures);
+        return;
+    }
+    printf("Test passed!\n");
+}
diff --git a/components/esp_mqtt_cxx/test/unit/sdkconfig.defaults b/components/esp_mqtt_cxx/test/unit/sdkconfig.defaults
new file mode 100644
index 0000000000..8bdcab28ad
--- /dev/null
+++ b/components/esp_mqtt_cxx/test/unit/sdkconfig.defaults
@@ -0,0 +1,4 @@
+CONFIG_COMPILER_CXX_EXCEPTIONS=y
+CONFIG_ESP_MAIN_TASK_STACK_SIZE=8192
+CONFIG_LWIP_PPP_SUPPORT=y
+CONFIG_PARTITION_TABLE_SINGLE_APP_LARGE=y
diff --git a/test_app/CMakeLists.txt b/test_app/CMakeLists.txt
index bda7a057a9..294b604fd6 100644
--- a/test_app/CMakeLists.txt
+++ b/test_app/CMakeLists.txt
@@ -7,7 +7,6 @@ include($ENV{IDF_PATH}/tools/cmake/version.cmake)
 set(EXTRA_COMPONENT_DIRS
     ../components/eppp_link
     ../components/esp_modem
-    ../components/esp_mqtt_cxx
     ../components/esp_websocket_client
     ../components/console_cmd_ifconfig
     ../components/console_cmd_ping