diff --git a/composer.json b/composer.json
index 71924b18e59..16533bc38f7 100644
--- a/composer.json
+++ b/composer.json
@@ -24,7 +24,7 @@
         "php-http/discovery": "^1.12",
         "php-http/httplug": "^2.2",
         "php-http/multipart-stream-builder": "^1.1.2",
-        "psr/cache": "^1.0|^2.0",
+        "psr/cache": "^1.0|^2.0|^3.0",
         "psr/http-client-implementation": "^1.0",
         "psr/http-factory-implementation": "^1.0",
         "psr/http-message": "^1.0",
@@ -54,5 +54,10 @@
             "dev-2.x": "2.20.x-dev",
             "dev-master": "3.4.x-dev"
         }
+    },
+    "config": {
+        "allow-plugins": {
+            "phpstan/extension-installer": true
+        }
     }
 }