diff --git a/httplib.h b/httplib.h
index f1e8d5c..da5c565 100644
--- a/httplib.h
+++ b/httplib.h
@@ -265,12 +265,20 @@ private:
   std::string buffer;
 };
 
-class ThreadsTaskQueue {
+class TaskQueue {
+public:
+  TaskQueue() {}
+  virtual ~TaskQueue() {}
+  virtual void enque(std::function<void(void)> fn) = 0;
+  virtual void shutdown() = 0;
+};
+
+class ThreadsTaskQueue : public TaskQueue {
 public:
   ThreadsTaskQueue() : running_threads_(0) {}
-  ~ThreadsTaskQueue() {}
+  virtual ~ThreadsTaskQueue() {}
 
-  void enque(std::function<void(void)> fn) {
+  virtual void enque(std::function<void(void)> fn) override {
     std::thread([=]() {
       {
         std::lock_guard<std::mutex> guard(running_threads_mutex_);
@@ -286,7 +294,7 @@ public:
     }).detach();
   }
 
-  void shutdown() {
+  virtual void shutdown() override {
     for (;;) {
       std::this_thread::sleep_for(std::chrono::milliseconds(10));
       std::lock_guard<std::mutex> guard(running_threads_mutex_);
@@ -299,8 +307,6 @@ private:
   int running_threads_;
 };
 
-typedef ThreadsTaskQueue TaskQueue;
-
 class Server {
 public:
   typedef std::function<void(const Request &, Response &)> Handler;
@@ -336,6 +342,8 @@ public:
   bool is_running() const;
   void stop();
 
+  std::function<TaskQueue*(void)> new_task_queue;
+
 protected:
   bool process_request(Stream &strm, bool last_connection,
                        bool &connection_close,
@@ -373,8 +381,6 @@ private:
   Handlers options_handlers_;
   Handler error_handler_;
   Logger logger_;
-
-  TaskQueue task_queue_;
 };
 
 class Client {
@@ -2226,40 +2232,48 @@ inline int Server::bind_internal(const char *host, int port, int socket_flags) {
 
 inline bool Server::listen_internal() {
   auto ret = true;
-
   is_running_ = true;
 
-  for (;;) {
-    if (svr_sock_ == INVALID_SOCKET) {
-      // The server socket was closed by 'stop' method.
-      break;
+  {
+    std::unique_ptr<TaskQueue> task_queue;
+
+    if (new_task_queue) {
+      task_queue.reset(new_task_queue());
+    } else {
+      task_queue.reset(new ThreadsTaskQueue());
     }
 
-    auto val = detail::select_read(svr_sock_, 0, 100000);
-
-    if (val == 0) { // Timeout
-      continue;
-    }
-
-    socket_t sock = accept(svr_sock_, nullptr, nullptr);
-
-    if (sock == INVALID_SOCKET) {
-      if (svr_sock_ != INVALID_SOCKET) {
-        detail::close_socket(svr_sock_);
-        ret = false;
-      } else {
-        ; // The server socket was closed by user.
+    for (;;) {
+      if (svr_sock_ == INVALID_SOCKET) {
+        // The server socket was closed by 'stop' method.
+        break;
       }
-      break;
+
+      auto val = detail::select_read(svr_sock_, 0, 100000);
+
+      if (val == 0) { // Timeout
+        continue;
+      }
+
+      socket_t sock = accept(svr_sock_, nullptr, nullptr);
+
+      if (sock == INVALID_SOCKET) {
+        if (svr_sock_ != INVALID_SOCKET) {
+          detail::close_socket(svr_sock_);
+          ret = false;
+        } else {
+          ; // The server socket was closed by user.
+        }
+        break;
+      }
+
+      task_queue->enque([=]() { read_and_close_socket(sock); });
     }
 
-    task_queue_.enque([=]() { read_and_close_socket(sock); });
+    task_queue->shutdown();
   }
 
-  task_queue_.shutdown();
-
   is_running_ = false;
-
   return ret;
 }