diff --git a/extension.neon b/extension.neon
index aa90e9d..6a5a290 100644
--- a/extension.neon
+++ b/extension.neon
@@ -65,6 +65,7 @@ services:
 		class: bitExpert\PHPStan\Magento\Autoload\Cache\FileCacheStorage
 		arguments:
 			directory: %tmpDir%/cache/PHPStan
+			magentoRoot: %magento.magentoRoot%
 	autoloaderCache:
 		autowired: false
 		class: PHPStan\Cache\Cache
diff --git a/src/bitExpert/PHPStan/Magento/Autoload/Cache/FileCacheStorage.php b/src/bitExpert/PHPStan/Magento/Autoload/Cache/FileCacheStorage.php
index 1447081..4d59462 100644
--- a/src/bitExpert/PHPStan/Magento/Autoload/Cache/FileCacheStorage.php
+++ b/src/bitExpert/PHPStan/Magento/Autoload/Cache/FileCacheStorage.php
@@ -21,14 +21,20 @@ class FileCacheStorage implements CacheStorage
      */
     private $directory;
 
+    /**
+     * @var string
+     */
+    private $magentoRoot;
+
     /**
      * FileCacheStorage constructor.
      *
      * @param string $directory
      */
-    public function __construct(string $directory)
+    public function __construct(string $directory, string $magentoRoot)
     {
         $this->directory = $directory;
+        $this->magentoRoot = $magentoRoot;
     }
 
     /**
@@ -73,7 +79,7 @@ public function save(string $key, string $variableKey, $data): void
      */
     private function getCacheDir(string $key): string
     {
-        $keyHash = sha1($key);
+        $keyHash = sha1(sprintf('%s/%s', $this->magentoRoot, $key));
         $firstDirectory = sprintf('%s/%s', $this->directory, substr($keyHash, 0, 2));
         return sprintf('%s/%s', $firstDirectory, substr($keyHash, 2, 2));
     }