diff --git a/composer.json b/composer.json
index 7bd2e55..f85f140 100644
--- a/composer.json
+++ b/composer.json
@@ -36,10 +36,7 @@
         "ext-simplexml": "*",
         "ext-xmlwriter": "*",
         "guzzlehttp/guzzle": "^6.3",
-        "danielstjules/stringy": "^3.1",
-        "mtdowling/jmespath.php": "^2.4",
         "adbario/php-dot-notation": "^2.2",
-        "clagiordano/weblibs-configmanager": "^1.0",
         "alibabacloud/tea": "^3.0"
     },
     "require-dev": {
diff --git a/src/Helper.php b/src/Helper.php
index 45438cf..6d9eab4 100644
--- a/src/Helper.php
+++ b/src/Helper.php
@@ -3,7 +3,6 @@
 namespace AlibabaCloud\Credentials;
 
 use Closure;
-use Stringy\Stringy;
 
 /**
  * Class Helper
@@ -67,7 +66,7 @@ public static function inOpenBasedir($filename)
     public static function inDir($filename, array $dirs)
     {
         foreach ($dirs as $dir) {
-            if (!Stringy::create($dir)->endsWith(DIRECTORY_SEPARATOR)) {
+            if ($dir[strlen($dir) - 1] !== DIRECTORY_SEPARATOR) {
                 $dir .= DIRECTORY_SEPARATOR;
             }
 
@@ -145,8 +144,8 @@ public static function value($value)
     public static function envSubstr($value)
     {
         return ($valueLength = strlen($value)) > 1
-               && strpos($value, '"') === 0
-               && $value[$valueLength - 1] === '"';
+            && strpos($value, '"') === 0
+            && $value[$valueLength - 1] === '"';
     }
 
     /**