diff --git a/src/Specs/ResourcesCacheStore.php b/src/Specs/ResourcesCacheStore.php
index 21d53bd5..2e371c38 100644
--- a/src/Specs/ResourcesCacheStore.php
+++ b/src/Specs/ResourcesCacheStore.php
@@ -9,7 +9,7 @@
 class ResourcesCacheStore
 {
     /** @var RegisteredResource[] */
-    protected array $resources = [];
+    protected $resources = [];
 
     public function addResource(RegisteredResource $resource): self
     {