diff --git a/src/Assert.php b/src/Assert.php
index 6062478..97ae9fb 100644
--- a/src/Assert.php
+++ b/src/Assert.php
@@ -40,7 +40,7 @@ public static function assertJsonMatchesSchema($schema, $content)
         // Assume references are relative to the current file
         // Create an issue or pull request if you need more complex use cases
         $refResolver = new RefResolver(new UriRetriever(), new UriResolver());
-        $schemaObj = $refResolver->resolve('file://' . realpath($schema));
+        $schemaObj = $refResolver->resolve('file://'.realpath($schema));
 
         $validator = new Validator();
         $validator->check($content, $schemaObj);