diff --git a/.gitignore b/.gitignore
index 63bd0d8..8a8ad5f 100644
--- a/.gitignore
+++ b/.gitignore
@@ -10,3 +10,4 @@ package-lock.json
 **/priv_note.md
 _priv_tools/
 project_components/wifi_manager/wifi_configuration.h
+managed_components/
\ No newline at end of file
diff --git a/components/global_resource/global_module.c b/components/global_resource/global_module.c
new file mode 100644
index 0000000..5dbf3c0
--- /dev/null
+++ b/components/global_resource/global_module.c
@@ -0,0 +1,44 @@
+/*
+ * SPDX-FileCopyrightText: 2024 kerms <kerms@niazo.org>
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include "global_module.h"
+#include <stddef.h>
+#include <esp_log.h>
+
+#define TAG __FILE_NAME__
+#define GLOBAL_MODULE_MAX 10
+
+static global_module_t module_arr[GLOBAL_MODULE_MAX] = {0};
+static uint8_t module_count = 0;
+
+int global_module_reg(const global_module_t *g_mod)
+{
+	if (g_mod->module_id > GLOBAL_MODULE_MAX) {
+		ESP_LOGE(TAG, "g_id > max");
+		return 1;
+	}
+
+	if (module_arr[g_mod->module_id].init != NULL) {
+		ESP_LOGE(TAG, "g_id.init not NULL");
+		return 1;
+	}
+
+	ESP_LOGI(TAG, "g_id: %d", g_mod->module_id);
+	module_arr[g_mod->module_id].module_id = g_mod->module_id;
+	module_arr[g_mod->module_id].init = g_mod->init;
+	module_count++;
+	return 0;
+}
+
+int global_module_init()
+{
+	for (int i = 0; i < GLOBAL_MODULE_MAX; ++i) {
+		if (module_arr[i].init) {
+			module_arr[i].init();
+		}
+	}
+	return 0;
+}
diff --git a/components/global_resource/global_module.h b/components/global_resource/global_module.h
new file mode 100644
index 0000000..b9d6a26
--- /dev/null
+++ b/components/global_resource/global_module.h
@@ -0,0 +1,28 @@
+/*
+ * SPDX-FileCopyrightText: 2024 kerms <kerms@niazo.org>
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#ifndef GLOBAL_MODULE_H_GUARD
+#define GLOBAL_MODULE_H_GUARD
+
+#include <stdint.h>
+
+typedef int (*global_module_init_func)(void);
+
+typedef struct global_module_t {
+	global_module_init_func init;
+	uint8_t module_id;
+} global_module_t;
+
+int global_module_reg(const global_module_t *g_mod);
+
+int global_module_init();
+
+#define GLOBAL_MODULE_REGISTER(NAME, GLOBAL_MODULE_CFG) \
+  __attribute__((used, constructor)) void cons_G_MOD_ ## NAME(); \
+  void cons_G_MOD_ ## NAME() { global_module_reg(GLOBAL_MODULE_CFG); }
+
+
+#endif //GLOBAL_MODULE_H_GUARD
\ No newline at end of file
diff --git a/project_components/static_buffer/CMakeLists.txt b/components/memory_pool/CMakeLists.txt
similarity index 100%
rename from project_components/static_buffer/CMakeLists.txt
rename to components/memory_pool/CMakeLists.txt
diff --git a/project_components/static_buffer/static_buffer.c b/components/memory_pool/memory_pool.c
similarity index 79%
rename from project_components/static_buffer/static_buffer.c
rename to components/memory_pool/memory_pool.c
index 257d022..4f90e44 100644
--- a/project_components/static_buffer/static_buffer.c
+++ b/components/memory_pool/memory_pool.c
@@ -4,17 +4,19 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
-#include "static_buffer.h"
+#include "memory_pool.h"
 #include <freertos/FreeRTOS.h>
 #include <freertos/queue.h>
 
-#define BUFFER_NR 4
+#define BUFFER_NR 8
 #define BUFFER_SZ 2048
 
 static uint8_t buf[BUFFER_NR][BUFFER_SZ];
+
+/* TODO: use CAS */
 static QueueHandle_t buf_queue = NULL;
 
-int static_buffer_init()
+int memory_pool_init()
 {
 	if (buf_queue != NULL)
 		return 0;
@@ -33,14 +35,14 @@ int static_buffer_init()
 	return 0;
 }
 
-void *static_buffer_get(uint32_t tick_wait)
+void *memory_pool_get(uint32_t tick_wait)
 {
 	void *ptr = NULL;
 	xQueueReceive(buf_queue, &ptr, tick_wait);
 	return ptr;
 }
 
-void static_buffer_put(void *ptr)
+void memory_pool_put(void *ptr)
 {
 	//printf("put buf %d\n", uxQueueMessagesWaiting(buf_queue));
 	if (unlikely(xQueueSend(buf_queue, &ptr, 0) != pdTRUE)) {
@@ -48,7 +50,7 @@ void static_buffer_put(void *ptr)
 	}
 }
 
-uint32_t static_buffer_get_buf_size()
+inline uint32_t memory_pool_get_buf_size()
 {
 	return BUFFER_SZ;
 }
diff --git a/project_components/static_buffer/static_buffer.h b/components/memory_pool/memory_pool.h
similarity index 50%
rename from project_components/static_buffer/static_buffer.h
rename to components/memory_pool/memory_pool.h
index 5aeaccf..676464a 100644
--- a/project_components/static_buffer/static_buffer.h
+++ b/components/memory_pool/memory_pool.h
@@ -9,13 +9,13 @@
 
 #include <stdint.h>
 
-int static_buffer_init();
+int memory_pool_init();
 
-void *static_buffer_get(uint32_t tick_wait);
+void *memory_pool_get(uint32_t tick_wait);
 
-void static_buffer_put(void *ptr);
+void memory_pool_put(void *ptr);
 
-uint32_t static_buffer_get_buf_size();
+uint32_t memory_pool_get_buf_size();
 
 
 #endif //STATIC_BUFFER_H_GUARD
\ No newline at end of file
diff --git a/main/main.c b/main/main.c
index 2cc4eb6..d28a2af 100644
--- a/main/main.c
+++ b/main/main.c
@@ -10,7 +10,7 @@
 #include "wt_storage.h"
 #include "wifi_manager.h"
 #include "web_server.h"
-#include "static_buffer.h"
+#include "memory_pool.h"
 #include "request_runner.h"
 #include "uart_tcp_bridge.h"
 
@@ -18,18 +18,17 @@
 
 void app_main()
 {
-	assert(static_buffer_init() == 0);
+	assert(memory_pool_init() == 0); // static buffer
 	assert(request_runner_init() == 0);
 	wt_storage_init();
 	ESP_ERROR_CHECK(esp_netif_init());
 	ESP_ERROR_CHECK(esp_event_loop_create_default());
+	wt_mdns_init();
 
 	wifi_manager_init();
     DAP_Setup();
 	start_webserver();
 
-	wt_mdns_init();
-
     xTaskCreate(tcp_server_task, "tcp_server", 4096, NULL, 14, NULL);
 
     // DAP handle task
diff --git a/project_components/api_router/CMakeLists.txt b/project_components/api_router/CMakeLists.txt
index b0d6fed..f077479 100644
--- a/project_components/api_router/CMakeLists.txt
+++ b/project_components/api_router/CMakeLists.txt
@@ -1,4 +1,4 @@
-file(GLOB SOURCES *
+file(GLOB SOURCES *.c
         )
 
 
diff --git a/project_components/api_router/api_json_module.h b/project_components/api_router/api_json_module.h
index 0c720d2..610739f 100644
--- a/project_components/api_router/api_json_module.h
+++ b/project_components/api_router/api_json_module.h
@@ -25,12 +25,13 @@ typedef enum api_json_req_status_e {
 	API_JSON_OK = 0,
 	API_JSON_ASYNC = 1,
 	API_JSON_BAD_REQUEST = 2,
+	API_JSON_INTERNAL_ERR = 3,
 } api_json_req_status_e;
 
 typedef int (*api_json_on_req)(uint16_t cmd, api_json_req_t *req, api_json_module_async_t *rsp);
 
 typedef struct api_json_module_cfg_t {
-	api_json_on_req on_req;
+	api_json_on_req on_req; /* input request callback */
 	uint8_t module_id;
 } api_json_module_cfg_t;
 
@@ -40,9 +41,6 @@ void api_json_module_dump();
 
 int api_json_module_add(api_json_init_func);
 
-/**
- * @brief Register a module that will be init with PRI(priority) order.
- */
 #define API_JSON_MODULE_REGISTER(PRI, INIT) \
   __attribute__((used, constructor(PRI))) void cons_ ## INIT(); \
   void cons_ ## INIT() { api_json_module_add(INIT); }
diff --git a/project_components/request_runner/request_runner.c b/project_components/request_runner/request_runner.c
index 6bc5413..9a34a99 100644
--- a/project_components/request_runner/request_runner.c
+++ b/project_components/request_runner/request_runner.c
@@ -26,7 +26,7 @@ _Noreturn void req_long_task(void *arg)
 		if (unlikely(xQueueReceive(long_run_queue, &req, portMAX_DELAY) != pdTRUE)) {
 			continue;
 		}
-		req->status = req->module.helper_cb(req->module.arg);
+		req->status = req->module.cb(req->module.arg);
 
 		/* if send out queue is busy, set status and let the cb to cancel send out
 		 * */
diff --git a/project_components/request_runner/request_runner.h b/project_components/request_runner/request_runner.h
index 7bff2a1..037252d 100644
--- a/project_components/request_runner/request_runner.h
+++ b/project_components/request_runner/request_runner.h
@@ -15,7 +15,7 @@ typedef struct req_send_out_cb_t {
 } req_send_out_cb_t;
 
 typedef struct req_module_cb_t {
-	int (*helper_cb)(void *arg);
+	int (*cb)(void *arg);
 	void *arg;
 } req_module_cb_t;
 
diff --git a/project_components/web_server/CMakeLists.txt b/project_components/web_server/CMakeLists.txt
index 08f8054..925ace4 100644
--- a/project_components/web_server/CMakeLists.txt
+++ b/project_components/web_server/CMakeLists.txt
@@ -10,7 +10,7 @@ idf_component_register(
         SRCS ${SOURCES}
         INCLUDE_DIRS "."
         REQUIRES esp_http_server
-        PRIV_REQUIRES request_runner api_router json static_buffer utils html
+        PRIV_REQUIRES request_runner api_router json memory_pool utils html
 )
 
 idf_component_set_property(${COMPONENT_NAME} WHOLE_ARCHIVE ON)
diff --git a/project_components/web_server/uri_modules/uri_api.c b/project_components/web_server/uri_modules/uri_api.c
index 4fd15b9..22f336e 100644
--- a/project_components/web_server/uri_modules/uri_api.c
+++ b/project_components/web_server/uri_modules/uri_api.c
@@ -1,7 +1,7 @@
 #include "web_uri_module.h"
 #include "api_json_router.h"
 #include "request_runner.h"
-#include "static_buffer.h"
+#include "memory_pool.h"
 
 #include <esp_http_server.h>
 #include <esp_log.h>
@@ -32,13 +32,13 @@ static esp_err_t api_post_handler(httpd_req_t *req)
 	char *buf;
 	uint32_t remaining = req->content_len;
 
-	buf_len = static_buffer_get_buf_size() - sizeof(post_request_t);
+	buf_len = memory_pool_get_buf_size() - sizeof(post_request_t);
 	if (unlikely(buf_len < remaining)) {
 		ESP_LOGE(TAG, "req size %lu > buf_len %lu", remaining, buf_len);
 		return ESP_FAIL;
 	}
 
-	post_req = static_buffer_get(pdMS_TO_TICKS(20));
+	post_req = memory_pool_get(pdMS_TO_TICKS(20));
 	if (unlikely(post_req == NULL)) {
 		ESP_LOGE(TAG, "static buf busy");
 		return ESP_FAIL;
@@ -97,7 +97,7 @@ end:
 		ESP_LOGE(TAG, "resp_send err: %s", esp_err_to_name(err));
 	}
 put_buf:
-	static_buffer_put(post_req);
+	memory_pool_put(post_req);
 	return err;
 }
 
@@ -107,7 +107,7 @@ int uri_api_send_out(httpd_req_t *req, post_request_t *post_req, int err)
 	uint32_t buf_len;
 
 	buf = post_req->buf;
-	buf_len = static_buffer_get_buf_size() - sizeof(post_request_t);
+	buf_len = memory_pool_get_buf_size() - sizeof(post_request_t);
 	cJSON_Delete(post_req->json.in);
 	if (post_req->json.out) {
 		ESP_LOGI(TAG, "json out ok");
@@ -136,7 +136,7 @@ void async_send_out_cb(void *arg, int module_status)
 
 	/* clean resources */
 	httpd_req_async_handler_complete(req->req_out);
-	static_buffer_put(req);
+	memory_pool_put(req);
 };
 
 /**
diff --git a/project_components/web_server/uri_modules/uri_ws.c b/project_components/web_server/uri_modules/uri_ws.c
index 113d243..3c2fb9d 100644
--- a/project_components/web_server/uri_modules/uri_ws.c
+++ b/project_components/web_server/uri_modules/uri_ws.c
@@ -6,7 +6,7 @@
 
 #include "web_uri_module.h"
 #include "api_json_router.h"
-#include "static_buffer.h"
+#include "memory_pool.h"
 
 #include <esp_http_server.h>
 #include <esp_log.h>
@@ -20,8 +20,11 @@
 #define TAG __FILE_NAME__
 #define MSG_BUSY_ERROR "{\"error\":\"Resource busy\"}"
 #define MSG_JSON_ERROR "{\"error\":\"JSON parse error\"}"
+#define MSG_BAD_REQUEST_ERROR "{\"error\":\"Bad json request\"}"
 #define MSG_SEND_JSON_ERROR "{\"error\":\"JSON generation error\"}"
-#define MSG_INTERNAL_ERROR "{\"error\":\"\"}"
+#define MSG_INTERNAL_ERROR "{\"error\":\"Internal error\"}"
+
+#define WS_MODULE_ID 3
 
 typedef struct ws_msg_t {
 	api_json_req_t json;
@@ -33,13 +36,13 @@ typedef struct ws_msg_t {
 	uint8_t payload[0]; /* size = static_buf_size - offsetof(this, delim) */
 } ws_msg_t;
 
-#define PAYLOAD_LEN static_buffer_get_buf_size() - sizeof(ws_msg_t)
+#define PAYLOAD_LEN memory_pool_get_buf_size() - sizeof(ws_msg_t)
 
 struct ws_ctx_t {
 	struct ws_client_info_t {
 		httpd_handle_t hd;
-		int fd; /* range 58 ~ 58+max_socket */
-	} clients[CONFIG_LWIP_MAX_SOCKETS+1];
+		int fd; /* range 64 - max_socket ~ 64 */
+	} clients[CONFIG_LWIP_MAX_SOCKETS + 1];
 	TaskHandle_t task_heartbeat;
 	int8_t client_count;
 } ws_ctx;
@@ -47,14 +50,14 @@ struct ws_ctx_t {
 static int ws_on_text_data(httpd_req_t *req, ws_msg_t *ws_msg);
 static int ws_on_binary_data(httpd_req_t *req, ws_msg_t *ws_msg);
 static int ws_on_socket_open(httpd_req_t *req);
-static int ws_on_close(httpd_req_t *req, ws_msg_t *msg);
+static int ws_on_close(httpd_req_t *req, httpd_ws_frame_t *ws_pkt, void *msg);
 
 static void ws_async_resp(void *arg);
 static void async_send_out_cb(void *arg, int module_status);
 static void json_to_text(ws_msg_t *msg);
 
 /* Heartbeat related */
-static inline void ws_add_fd(httpd_handle_t hd, int fd);
+static inline int8_t ws_add_fd(httpd_handle_t hd, int fd);
 static inline void ws_rm_fd(int fd);
 
 _Noreturn static void heartbeat_task(void *arg);
@@ -69,13 +72,13 @@ static esp_err_t ws_req_handler(httpd_req_t *req)
 
 	ESP_LOGI(TAG, "ws_handler: httpd_handle_t=%p, sockfd=%d, client_info:%d, client_count: %d", req->handle,
 	         httpd_req_to_sockfd(req), httpd_ws_get_fd_info(req->handle, httpd_req_to_sockfd(req)),
-			 ws_ctx.client_count);
+	         ws_ctx.client_count);
 
 	int err = ESP_OK;
 	httpd_ws_frame_t *ws_pkt;
 	ws_msg_t *ws_msg;
 
-	ws_msg = static_buffer_get(pdMS_TO_TICKS(10));
+	ws_msg = memory_pool_get(pdMS_TO_TICKS(10));
 	if (unlikely(ws_msg == NULL)) {
 		httpd_ws_frame_t resp_pkt;
 		resp_pkt.type = HTTPD_WS_TYPE_TEXT;
@@ -92,12 +95,12 @@ static esp_err_t ws_req_handler(httpd_req_t *req)
 	err = httpd_ws_recv_frame(req, ws_pkt, 0);
 	if (unlikely(err != ESP_OK)) {
 		ESP_LOGE(TAG, "ws recv len error");
-		return ws_on_close(req, ws_msg);
+		return ws_on_close(req, ws_pkt, ws_msg);
 	}
 	ESP_LOGI(TAG, "frame len: %d, type: %d", ws_pkt->len, ws_pkt->type);
 	if (unlikely(ws_pkt->len > PAYLOAD_LEN)) {
 		ESP_LOGE(TAG, "frame len is too big");
-		return ws_on_close(req, ws_msg);
+		return ws_on_close(req, ws_pkt, ws_msg);
 	}
 
 	switch (ws_pkt->type) {
@@ -109,20 +112,13 @@ static esp_err_t ws_req_handler(httpd_req_t *req)
 		err = httpd_ws_recv_frame(req, ws_pkt, ws_pkt->len);
 		if (unlikely(err != ESP_OK)) {
 			ESP_LOGE(TAG, "ws recv data error");
-			return ws_on_close(req, ws_msg);
+			return ws_on_close(req, ws_pkt, ws_msg);
 		}
 		return ws_on_text_data(req, ws_msg);
 	case HTTPD_WS_TYPE_BINARY:
-		ws_pkt->payload = ws_msg->payload;
-		/* read incoming data */
-		err = httpd_ws_recv_frame(req, ws_pkt, ws_pkt->len);
-		if (unlikely(err != ESP_OK)) {
-			ESP_LOGE(TAG, "ws recv data error");
-			return ws_on_close(req, ws_msg);
-		}
 		return ws_on_binary_data(req, ws_msg);
 	case HTTPD_WS_TYPE_CLOSE:
-		return ws_on_close(req, ws_msg);
+		return ws_on_close(req, ws_pkt, ws_msg);
 	case HTTPD_WS_TYPE_PING:
 		/* Now turn the frame to PONG */
 		ws_pkt->type = HTTPD_WS_TYPE_PONG;
@@ -136,39 +132,11 @@ static esp_err_t ws_req_handler(httpd_req_t *req)
 		goto end;
 	}
 end:
-	static_buffer_put(ws_msg);
+	memory_pool_put(ws_msg);
 	return err;
 }
 
-
-/**
- * REGISTER MODULE
- * */
-
-static const httpd_uri_t uri_api = {
-	.uri       = "/ws",
-	.method    = HTTP_GET,
-	.handler   = ws_req_handler,
-	.user_ctx  = NULL,
-	.is_websocket = true,
-	.supported_subprotocol = NULL,
-	.handle_ws_control_frames = true,
-};
-
-static int WS_REQ_INIT(const httpd_uri_t **uri_conf) {
-	*uri_conf = &uri_api;
-	xTaskCreate(heartbeat_task, "hb task", 2048, NULL, 3, &ws_ctx.task_heartbeat);
-	return 0;
-}
-
-static int WS_REQ_EXIT(const httpd_uri_t **uri_conf) {
-	*uri_conf = &uri_api;
-	vTaskDelete(ws_ctx.task_heartbeat);
-	ws_ctx.task_heartbeat = NULL;
-	return 0;
-}
-
-WEB_URI_MODULE_REGISTER(101, WS_REQ_INIT, WS_REQ_EXIT)
+void ws_set_err_msg(httpd_ws_frame_t *p_frame, api_json_req_status_e ret);
 
 int ws_on_text_data(httpd_req_t *req, ws_msg_t *ws_msg)
 {
@@ -183,9 +151,9 @@ int ws_on_text_data(httpd_req_t *req, ws_msg_t *ws_msg)
 	ESP_LOGI(TAG, "heap min: %lu, cur: %lu", esp_get_minimum_free_heap_size(), esp_get_free_heap_size());
 
 	/* Decode */
-	ws_msg->json.in = cJSON_ParseWithLength((char *) ws_pkt->payload, ws_pkt->len);
+	ws_msg->json.in = cJSON_ParseWithLength((char *)ws_pkt->payload, ws_pkt->len);
 	if (unlikely(ws_msg->json.in == NULL)) {
-		ws_pkt->payload = (uint8_t *) MSG_JSON_ERROR;
+		ws_pkt->payload = (uint8_t *)MSG_JSON_ERROR;
 		ws_pkt->len = strlen(MSG_JSON_ERROR);
 		goto put_buf;
 	}
@@ -204,10 +172,7 @@ int ws_on_text_data(httpd_req_t *req, ws_msg_t *ws_msg)
 		/* ret, buf will be release latter in async send out */
 		return ESP_OK;
 	} else if (ret != API_JSON_OK) {
-		ws_pkt->len = strlen(MSG_BUSY_ERROR);
-		ws_pkt->payload = (uint8_t *)MSG_BUSY_ERROR;
-		ws_pkt->final = 1;
-		err = httpd_ws_send_frame_async(req->handle, httpd_req_to_sockfd(req), ws_pkt);
+		ws_set_err_msg(ws_pkt, ret);
 		goto end;
 	} else if (ws_msg->json.out == NULL) {
 		goto end;
@@ -220,39 +185,62 @@ end:
 	cJSON_Delete(ws_msg->json.in);
 put_buf:
 	httpd_ws_send_frame_async(req->handle, httpd_req_to_sockfd(req), ws_pkt);
-	static_buffer_put(ws_msg);
+	memory_pool_put(ws_msg);
 	return err;
 }
 
+void ws_set_err_msg(httpd_ws_frame_t *p_frame, api_json_req_status_e ret)
+{
+	switch (ret) {
+	case API_JSON_BAD_REQUEST:
+		p_frame->len = strlen(MSG_BAD_REQUEST_ERROR);
+		p_frame->payload = (uint8_t *)MSG_BAD_REQUEST_ERROR;
+		p_frame->final = 1;
+		break;
+	case API_JSON_INTERNAL_ERR:
+		p_frame->len = strlen(MSG_INTERNAL_ERROR);
+		p_frame->payload = (uint8_t *)MSG_INTERNAL_ERROR;
+		p_frame->final = 1;
+		break;
+	default:
+		return;
+	}
+}
+
+_Static_assert(sizeof(httpd_ws_frame_t) <= 16, "bin_data_internal padding not sufficient for httpd_ws_frame_t");
+
 int ws_on_binary_data(httpd_req_t *req, ws_msg_t *ws_msg)
 {
 	(void) req;
-	static_buffer_put(ws_msg);
+	memory_pool_put(ws_msg);
 	return 0;
 }
 
 int ws_on_socket_open(httpd_req_t *req)
 {
 	int sock_fd = httpd_req_to_sockfd(req);
-	ws_add_fd(req->handle, sock_fd);
 	ESP_LOGI(TAG, "ws open: %d", sock_fd);
-	return ESP_OK;
+	return ws_add_fd(req->handle, sock_fd);
 }
 
-static int ws_on_close(httpd_req_t *req, ws_msg_t *msg)
+/**
+ * @param msg must only used as generic ptr, truncated by ws_on_bin()
+ * @return
+ */
+static int ws_on_close(httpd_req_t *req, httpd_ws_frame_t *ws_pkt, void *msg)
 {
 	/* Read the rest of the CLOSE frame and response */
 	/* Please refer to RFC6455 Section 5.5.1 for more details */
-	msg->ws_pkt.len = 0;
-	msg->ws_pkt.type = HTTPD_WS_TYPE_CLOSE;
+	ws_pkt->len = 0;
+	ws_pkt->type = HTTPD_WS_TYPE_CLOSE;
 	ESP_LOGI(TAG, "ws %d closed", httpd_req_to_sockfd(req));
 	ws_rm_fd(httpd_req_to_sockfd(req));
-	int err = httpd_ws_send_frame(req, &msg->ws_pkt);
+	int err = httpd_ws_send_frame(req, ws_pkt);
 	if (err) {
 		ESP_LOGE(TAG, "on close %s", esp_err_to_name(err));
 	}
 	httpd_sess_trigger_close(req->handle, httpd_req_to_sockfd(req));
-	static_buffer_put(msg);
+	memory_pool_put(msg);
 	return err;
 }
 
@@ -265,10 +253,10 @@ static void ws_async_resp(void *arg)
 
 	ESP_LOGI(TAG, "ws async fd : %d", fd);
 	err = httpd_ws_send_frame_async(hd, fd, &req->ws_pkt);
-	if (err) {
+	if (unlikely(err)) {
 		ESP_LOGE(TAG, "%s", esp_err_to_name(err));
 	}
-	static_buffer_put(req);
+	memory_pool_put(req);
 }
 
 void async_send_out_cb(void *arg, int module_status)
@@ -282,6 +270,7 @@ void async_send_out_cb(void *arg, int module_status)
 	json_to_text(req);
 	err = httpd_queue_work(req->hd, ws_async_resp, req);
 	if (likely(err == ESP_OK)) {
+		/* msg queued, let callee release the buffer */
 		return;
 	}
 
@@ -289,7 +278,7 @@ void async_send_out_cb(void *arg, int module_status)
 
 end:
 	/* clean resources */
-	static_buffer_put(req);
+	memory_pool_put(req);
 }
 
 void json_to_text(ws_msg_t *ws_msg)
@@ -297,27 +286,29 @@ void json_to_text(ws_msg_t *ws_msg)
 	int err;
 	httpd_ws_frame_t *ws_pkt = &ws_msg->ws_pkt;
 	/* api function returns something, send it to http client */
-	err = !cJSON_PrintPreallocated(ws_msg->json.out, (char *) ws_msg->payload, PAYLOAD_LEN - 5, 0);
+	err = !cJSON_PrintPreallocated(ws_msg->json.out, (char *)ws_msg->payload, PAYLOAD_LEN - 5, 0);
 	cJSON_Delete(ws_msg->json.out);
 	if (unlikely(err)) {
 		ws_pkt->len = strlen(MSG_SEND_JSON_ERROR);
-		ws_pkt->payload = (uint8_t *) MSG_SEND_JSON_ERROR;
+		ws_pkt->payload = (uint8_t *)MSG_SEND_JSON_ERROR;
 		ws_pkt->final = 1;
 	}
-	ws_pkt->len = strlen((char *) ws_pkt->payload);
+	ws_pkt->len = strlen((char *)ws_pkt->payload);
 }
 
 
 /* Clients array manipulation function
  * */
-static inline void ws_add_fd(httpd_handle_t hd, int fd)
+static inline int8_t ws_add_fd(httpd_handle_t hd, int fd)
 {
 	if (ws_ctx.client_count > CONFIG_LWIP_MAX_SOCKETS) {
-		return;
+		return 1;
 	}
+
 	ws_ctx.clients[ws_ctx.client_count].fd = fd;
 	ws_ctx.clients[ws_ctx.client_count].hd = hd;
 	ws_ctx.client_count++;
+	return 0;
 }
 
 /**
@@ -328,8 +319,8 @@ static inline void ws_rm_fd(int fd)
 {
 	for (int i = 0; i < ws_ctx.client_count; ++i) {
 		if (ws_ctx.clients[i].fd == fd) {
-			ws_ctx.clients[i].fd = ws_ctx.clients[ws_ctx.client_count-1].fd;
-			ws_ctx.clients[i].hd = ws_ctx.clients[ws_ctx.client_count-1].hd;
+			ws_ctx.clients[i].fd = ws_ctx.clients[ws_ctx.client_count - 1].fd;
+			ws_ctx.clients[i].hd = ws_ctx.clients[ws_ctx.client_count - 1].hd;
 			ws_ctx.client_count--;
 			return;
 		}
@@ -368,10 +359,41 @@ static inline void ws_broadcast_heartbeat()
 _Noreturn
 void heartbeat_task(void *arg)
 {
-	(void) arg;
+	(void)arg;
 	while (1) {
 		vTaskDelay(pdMS_TO_TICKS(2000));
 		ws_broadcast_heartbeat();
 	}
 };
 
+
+/**
+ * REGISTER MODULE
+ * */
+
+static const httpd_uri_t uri_api = {
+	.uri       = "/ws",
+	.method    = HTTP_GET,
+	.handler   = ws_req_handler,
+	.user_ctx  = NULL,
+	.is_websocket = true,
+	.supported_subprotocol = NULL,
+	.handle_ws_control_frames = true,
+};
+
+static int WS_REQ_INIT(const httpd_uri_t **uri_conf)
+{
+	*uri_conf = &uri_api;
+	xTaskCreate(heartbeat_task, "hb task", 2048, NULL, 3, &ws_ctx.task_heartbeat);
+	return 0;
+}
+
+static int WS_REQ_EXIT(const httpd_uri_t **uri_conf)
+{
+	*uri_conf = &uri_api;
+	vTaskDelete(ws_ctx.task_heartbeat);
+	ws_ctx.task_heartbeat = NULL;
+	return 0;
+}
+
+WEB_URI_MODULE_REGISTER(101, WS_REQ_INIT, WS_REQ_EXIT)
diff --git a/project_components/web_server/web_uri_module.h b/project_components/web_server/web_uri_module.h
index 6181a86..f2a85c9 100644
--- a/project_components/web_server/web_uri_module.h
+++ b/project_components/web_server/web_uri_module.h
@@ -11,10 +11,15 @@ typedef struct uri_module_t {
 	uint8_t priority;
 } uri_module_t;
 
+/**
+ * @param priority smaller number will be called first
+ * @return 0: SUCCESS, 1: max module count reached
+ */
 int uri_module_add(uint8_t priority, uri_module_func init, uri_module_func exit);
 
 /**
  * @brief Register a uri module that will be init with PRI(priority) order.
+ * smaller priority will be called first.
  */
 #define WEB_URI_MODULE_REGISTER(PRI, INIT, EXIT) \
   __attribute__((used, constructor(PRI))) void cons_ ## INIT(); \
diff --git a/project_components/wifi_manager/wifi_api.h b/project_components/wifi_manager/wifi_api.h
index 2caddb3..52bbc59 100644
--- a/project_components/wifi_manager/wifi_api.h
+++ b/project_components/wifi_manager/wifi_api.h
@@ -3,7 +3,7 @@
 
 #include <lwip/ip4_addr.h>
 
-#define WIFI_API_MODULE_ID 1
+#define WIFI_MODULE_ID 1
 
 typedef enum wifi_api_json_cmd_t {
 	UNKNOWN = 0,
diff --git a/project_components/wifi_manager/wifi_api_json.c b/project_components/wifi_manager/wifi_api_json.c
index 522ccc7..2247c9e 100644
--- a/project_components/wifi_manager/wifi_api_json.c
+++ b/project_components/wifi_manager/wifi_api_json.c
@@ -19,7 +19,7 @@ static int wifi_api_json_disconnect(api_json_req_t *req);
 
 static int wifi_api_json_ap_get_info(api_json_req_t *req);
 
-
+/* the upper caller call cb() with void *, this let us use custom function arg */
 static int async_helper_cb(void *arg)
 {
 	api_json_module_req_t *req = arg;
@@ -30,7 +30,7 @@ static inline int set_async(api_json_req_t *req, api_json_module_async_t *async,
 {
 	async->module.func = func;
 	async->module.arg = req;
-	async->req_task.module.helper_cb = async_helper_cb;
+	async->req_task.module.cb = async_helper_cb;
 	async->req_task.module.arg = &async->module;
 	return API_JSON_ASYNC;
 }
@@ -52,7 +52,6 @@ static int on_json_req(uint16_t cmd, api_json_req_t *req, api_json_module_async_
 		return wifi_api_json_disconnect(req);
 	case WIFI_API_JSON_AP_GET_INFO:
 		return wifi_api_json_ap_get_info(req);
-		break;
 	}
 
 	ESP_LOGI(TAG, "cmd %d not executed\n", cmd);
@@ -127,7 +126,7 @@ int wifi_api_json_disconnect(api_json_req_t *req)
 static int wifi_api_json_init(api_json_module_cfg_t *cfg)
 {
 	cfg->on_req = on_json_req;
-	cfg->module_id = WIFI_API_MODULE_ID;
+	cfg->module_id = WIFI_MODULE_ID;
 	return 0;
 }
 
diff --git a/project_components/wifi_manager/wifi_json_utils.c b/project_components/wifi_manager/wifi_json_utils.c
index c34cd39..24df07c 100644
--- a/project_components/wifi_manager/wifi_json_utils.c
+++ b/project_components/wifi_manager/wifi_json_utils.c
@@ -6,7 +6,7 @@
 static void wifi_api_json_set_header(cJSON *root, uint16_t cmd)
 {
 	cJSON_AddNumberToObject(root, "cmd", cmd);
-	cJSON_AddNumberToObject(root, "module", WIFI_API_MODULE_ID);
+	cJSON_AddNumberToObject(root, "module", WIFI_MODULE_ID);
 }
 
 cJSON *wifi_api_json_serialize_ap_info(wifi_api_ap_info_t *ap_info, wifi_api_json_cmd_t cmd)
diff --git a/project_components/wt_mdns/wt_mdns_config.c b/project_components/wt_mdns/wt_mdns_config.c
index baf5635..7f1f8ac 100644
--- a/project_components/wt_mdns/wt_mdns_config.c
+++ b/project_components/wt_mdns/wt_mdns_config.c
@@ -14,6 +14,22 @@ void wt_mdns_init()
 
 	/* TODO: read instance description from NVS */
 	ESP_ERROR_CHECK(mdns_instance_name_set(MDSN_INSTANCE_DESC));
+
+	//structure with TXT records
+	mdns_txt_item_t serviceTxtData[] = {
+#if defined CONFIG_IDF_TARGET_ESP32S3
+		{"board", "esp32S3"},
+#elif defined CONFIG_IDF_TARGET_ESP32C3
+		{"board", "esp32c3"},
+#elif defined CONFIG_IDF_TARGET_ESP32
+		{"board", "esp32"},
+#endif
+	};
+
+	//initialize service
+	ESP_ERROR_CHECK(mdns_service_add("WebServer", "_http", "_tcp", 80,
+									  serviceTxtData, sizeof(serviceTxtData)/sizeof(serviceTxtData[0])));
+	ESP_ERROR_CHECK(mdns_service_subtype_add_for_host("WebServer", "_http", "_tcp", NULL, "_server") );
 }
 
 int wt_mdns_set_hostname(const char *hostname)
diff --git a/project_components/wt_mdns/wt_mdns_config.h b/project_components/wt_mdns/wt_mdns_config.h
index c5a0516..7820516 100644
--- a/project_components/wt_mdns/wt_mdns_config.h
+++ b/project_components/wt_mdns/wt_mdns_config.h
@@ -2,7 +2,7 @@
 #define WT_MDNS_CONFIG_H_GUARD
 
 #define MDSN_DEFAULT_HOSTNAME "dap" // + serial number (4 char)
-#define MDSN_INSTANCE_DESC "无线STM32调试器 by 允斯工作室"
+#define MDSN_INSTANCE_DESC "ESP32 无线透传"
 
 void wt_mdns_init();