diff --git a/src/Config.php b/src/Config.php
index 3ea8a9c..9dfa70c 100644
--- a/src/Config.php
+++ b/src/Config.php
@@ -31,6 +31,7 @@ public function getRules() : array {
 			'elseif' => true,
 			'encoding' => true,
 			'full_opening_tag' => true,
+			'fully_qualified_strict_types' => ['leading_backslash_in_global_namespace' => true],
 			'function_declaration' => [
 				'closure_function_spacing' => 'one',
 			],