diff --git a/src/WpOrg/Api/Cache.php b/src/WpOrg/Api/Cache.php
index d658fee..d9a907a 100644
--- a/src/WpOrg/Api/Cache.php
+++ b/src/WpOrg/Api/Cache.php
@@ -41,7 +41,7 @@ public function write(string $slug, bool $isClosed): void
         }
 
         $content = sprintf(
-            "%s%s%s%s%s%s",
+            '%s%s%s%s%s%s',
             $isClosed ? 'closed' : 'open',
             PHP_EOL,
             $slug,