diff --git a/include/ylt/coro_io/client_pool.hpp b/include/ylt/coro_io/client_pool.hpp
index 96e20db60..9b4eb6d1d 100644
--- a/include/ylt/coro_io/client_pool.hpp
+++ b/include/ylt/coro_io/client_pool.hpp
@@ -298,8 +298,10 @@ class client_pool : public std::enable_shared_from_this<
             this->weak_from_this(), clients,
             (std::max)(collect_time, std::chrono::milliseconds{50}),
             pool_config_.idle_queue_per_max_clear_count)
-            .directlyStart([](auto&&) {
-            },coro_io::get_global_executor());
+            .directlyStart(
+                [](auto&&) {
+                },
+                coro_io::get_global_executor());
       }
     }
   }
@@ -372,6 +374,13 @@ class client_pool : public std::enable_shared_from_this<
                                          pool_config, io_context_pool);
   }
 
+  static std::unique_ptr<client_pool> create_unique(
+      std::string_view host_name, const pool_config& pool_config = {},
+      io_context_pool_t& io_context_pool = coro_io::g_io_context_pool()) {
+    return std::make_unique<client_pool>(private_construct_token{}, host_name,
+                                         pool_config, io_context_pool);
+  }
+
   client_pool(private_construct_token t, std::string_view host_name,
               const pool_config& pool_config,
               io_context_pool_t& io_context_pool)
diff --git a/include/ylt/easylog.hpp b/include/ylt/easylog.hpp
index aa7f1f76c..d429735f7 100644
--- a/include/ylt/easylog.hpp
+++ b/include/ylt/easylog.hpp
@@ -68,10 +68,11 @@ class logger {
   void init(Severity min_severity, bool async, bool enable_console,
             const std::string &filename, size_t max_file_size, size_t max_files,
             bool flush_every_time) {
-    static appender appender(filename, async, enable_console, max_file_size,
-                             max_files, flush_every_time);
+    static auto app =
+        std::make_shared<appender>(filename, async, enable_console,
+                                   max_file_size, max_files, flush_every_time);
     async_ = async;
-    appender_ = &appender;
+    appender_ = app;
     min_severity_ = min_severity;
     enable_console_ = enable_console;
   }
@@ -105,11 +106,11 @@ class logger {
 
  private:
   logger() {
-    static appender appender{};
-    appender.start_thread();
-    appender.enable_console(true);
+    static auto app = std::make_shared<appender>();
+    app->start_thread();
+    app->enable_console(true);
     async_ = true;
-    appender_ = &appender;
+    appender_ = app;
   }
 
   logger(const logger &) = default;
@@ -135,7 +136,7 @@ class logger {
 #endif
   bool async_ = false;
   bool enable_console_ = true;
-  appender *appender_ = nullptr;
+  std::shared_ptr<appender> appender_ = nullptr;
   std::vector<std::function<void(std::string_view)>> appenders_;
 };
 
diff --git a/include/ylt/standalone/cinatra/coro_http_client.hpp b/include/ylt/standalone/cinatra/coro_http_client.hpp
index c10e535c5..480ef7842 100644
--- a/include/ylt/standalone/cinatra/coro_http_client.hpp
+++ b/include/ylt/standalone/cinatra/coro_http_client.hpp
@@ -32,6 +32,7 @@
 #include "brzip.hpp"
 #endif
 #include "cinatra_log_wrapper.hpp"
+#include "error.hpp"
 #include "http_parser.hpp"
 #include "multipart.hpp"
 #include "picohttpparser.h"
@@ -351,7 +352,7 @@ class coro_http_client : public std::enable_shared_from_this<coro_http_client> {
       data = co_await connect(u, eps);
     }
     if (socket_->is_timeout_) {
-      co_return resp_data{std::make_error_code(std::errc::timed_out), 404};
+      co_return resp_data{make_error_code(http_errc::connect_timeout), 404};
     }
     if (!data.net_err) {
       data.status = 200;
@@ -1087,7 +1088,7 @@ class coro_http_client : public std::enable_shared_from_this<coro_http_client> {
       data = co_await connect(u);
     }
     if (socket_->is_timeout_) {
-      data = resp_data{std::make_error_code(std::errc::timed_out), 404};
+      data = resp_data{make_error_code(http_errc::connect_timeout), 404};
     }
     if (data.net_err) {
       co_return false;
@@ -1103,7 +1104,7 @@ class coro_http_client : public std::enable_shared_from_this<coro_http_client> {
     }
 #endif
     if (socket_->is_timeout_) {
-      ec = std::make_error_code(std::errc::timed_out);
+      ec = make_error_code(http_errc::request_timeout);
     }
   }
 
@@ -1374,7 +1375,7 @@ class coro_http_client : public std::enable_shared_from_this<coro_http_client> {
           co_await handle_read(ec, size, is_keep_alive, std::move(ctx), method);
     } while (0);
     if (ec && socket_->is_timeout_) {
-      ec = std::make_error_code(std::errc::timed_out);
+      ec = make_error_code(http_errc::request_timeout);
     }
     handle_result(data, ec, is_keep_alive);
     co_return data;
@@ -2050,7 +2051,7 @@ class coro_http_client : public std::enable_shared_from_this<coro_http_client> {
       }
 #endif
       if (socket_->is_timeout_) {
-        ec = std::make_error_code(std::errc::timed_out);
+        ec = make_error_code(http_errc::connect_timeout);
         co_return resp_data{ec, 404};
       }
 
@@ -2194,7 +2195,7 @@ class coro_http_client : public std::enable_shared_from_this<coro_http_client> {
               sock, read_buf, ws.left_header_len(), has_init_ssl);
           ec) {
         if (socket_->is_timeout_) {
-          co_return resp_data{std::make_error_code(std::errc::timed_out), 404};
+          co_return resp_data{make_error_code(http_errc::request_timeout), 404};
         }
         data.net_err = ec;
         data.status = 404;
diff --git a/include/ylt/standalone/cinatra/error.hpp b/include/ylt/standalone/cinatra/error.hpp
new file mode 100644
index 000000000..3ebcb9bc3
--- /dev/null
+++ b/include/ylt/standalone/cinatra/error.hpp
@@ -0,0 +1,37 @@
+#pragma once
+#include <string>
+#include <system_error>
+
+namespace cinatra {
+enum class http_errc { connect_timeout = 313, request_timeout };
+
+class http_error_category : public std::error_category {
+ public:
+  const char* name() const noexcept override { return "coro_http_error"; }
+
+  std::string message(int ev) const override {
+    switch (static_cast<http_errc>(ev)) {
+      case http_errc::connect_timeout:
+        return "connect timeout";
+      case http_errc::request_timeout:
+        return "request timeout";
+      default:
+        return "unknown error";
+    }
+  }
+};
+
+inline cinatra::http_error_category& category() {
+  static cinatra::http_error_category instance;
+  return instance;
+}
+
+inline std::error_code make_error_code(http_errc e) {
+  return {static_cast<int>(e), category()};
+}
+
+inline bool operator==(const std::error_code& code, http_errc ec) {
+  return code.value() == (int)ec;
+}
+
+}  // namespace cinatra
diff --git a/src/coro_http/tests/test_cinatra.cpp b/src/coro_http/tests/test_cinatra.cpp
index aed5d59df..6c8988ba5 100644
--- a/src/coro_http/tests/test_cinatra.cpp
+++ b/src/coro_http/tests/test_cinatra.cpp
@@ -83,7 +83,7 @@ TEST_CASE("test for gzip") {
     auto result = async_simple::coro::syncAwait(
         client.connect(uri).via(&client.get_executor()));
     if (result.net_err)
-      CHECK(result.net_err == std::errc::timed_out);
+      CHECK(result.net_err == http_errc::connect_timeout);
 
     client.set_conn_timeout(-1ms);
     client.set_req_timeout(0ms);
@@ -96,7 +96,7 @@ TEST_CASE("test for gzip") {
     result = async_simple::coro::syncAwait(
         client.async_get("/none").via(&client.get_executor()));
     if (result.net_err)
-      CHECK(result.net_err == std::errc::timed_out);
+      CHECK(result.net_err == http_errc::request_timeout);
 
     client.add_header("Content-Encoding", "none");
     client.set_req_timeout(-1ms);
@@ -113,7 +113,7 @@ TEST_CASE("test for gzip") {
     result = async_simple::coro::syncAwait(
         client.async_get(uri).via(&client.get_executor()));
     if (result.net_err)
-      CHECK(result.net_err == std::errc::timed_out);
+      CHECK(result.net_err == http_errc::request_timeout);
   }
 
   {
@@ -2575,7 +2575,7 @@ TEST_CASE("test coro_http_client request timeout") {
   if (!r.net_err) {
     r = async_simple::coro::syncAwait(client.async_get("/"));
     if (r.net_err) {
-      CHECK(r.net_err == std::errc::timed_out);
+      CHECK(r.net_err == http_errc::request_timeout);
     }
   }
 }
@@ -2770,7 +2770,7 @@ TEST_CASE("test coro http request timeout") {
 
   client.set_req_timeout(500ms);
   result = async_simple::coro::syncAwait(client.async_get(uri));
-  CHECK(result.net_err == std::errc::timed_out);
+  CHECK(result.net_err == http_errc::request_timeout);
 
   // after timeout, the socket in client has been closed, so use a new client
   // to test.
diff --git a/src/coro_http/tests/test_cinatra_websocket.cpp b/src/coro_http/tests/test_cinatra_websocket.cpp
index ed15970f6..f10782eaf 100644
--- a/src/coro_http/tests/test_cinatra_websocket.cpp
+++ b/src/coro_http/tests/test_cinatra_websocket.cpp
@@ -147,7 +147,7 @@ TEST_CASE("test websocket") {
     co_await client.write_websocket("hello websocket");
     auto data = co_await client.read_websocket();
     CINATRA_LOG_DEBUG << data.net_err.message();
-    CHECK(data.net_err == std::errc::timed_out);
+    CHECK(data.net_err == http_errc::request_timeout);
   };
 
   async_simple::coro::syncAwait(client_timeout());