diff --git a/src/Adapter/Swoole/EventLoop.php b/src/Adapter/Swoole/EventLoop.php
index 9132e76..bbaf8ba 100644
--- a/src/Adapter/Swoole/EventLoop.php
+++ b/src/Adapter/Swoole/EventLoop.php
@@ -9,6 +9,8 @@
 use M6Web\Tornado\Promise;
 use Swoole\Coroutine;
 use Swoole\Event;
+use RuntimeException;
+use function extension_loaded;
 
 class EventLoop implements \M6Web\Tornado\EventLoop
 {
@@ -20,6 +22,12 @@ class EventLoop implements \M6Web\Tornado\EventLoop
 
     public function __construct()
     {
+        if (!extension_loaded('swoole')) {
+            throw new RuntimeException(
+                'SwoolePromise MUST running only in CLI mode with swoole extension.'
+            );
+        }
+
         $this->streamLoop = new Internal\StreamEventLoop();
         $this->unhandledFailingPromises = new FailingPromiseCollection();
     }
diff --git a/src/Adapter/Swoole/Internal/SwoolePromise.php b/src/Adapter/Swoole/Internal/SwoolePromise.php
index a38ac15..1a44749 100644
--- a/src/Adapter/Swoole/Internal/SwoolePromise.php
+++ b/src/Adapter/Swoole/Internal/SwoolePromise.php
@@ -4,12 +4,8 @@
 
 use M6Web\Tornado\Promise;
 use Swoole\Coroutine;
-use Swoole\Coroutine\Channel;
 use RuntimeException;
-use function extension_loaded;
 use function count;
-use function is_callable;
-use function usleep;
 
 /**
  * @internal
@@ -30,12 +26,6 @@ final class SwoolePromise implements Promise
      */
     public function __construct(callable $executor)
     {
-        if (!extension_loaded('swoole')) {
-            throw new RuntimeException(
-                'SwoolePromise MUST running only in CLI mode with swoole extension.'
-            );
-        }
-
         $this->onResolve = function($status, $value) {
             $this->result = [$status, $value];
         };