diff --git a/src/State.php b/src/State.php
index cff9f17..df95515 100644
--- a/src/State.php
+++ b/src/State.php
@@ -39,7 +39,10 @@ public static function deserialize(string $json): State
 
     public static function serialize(State $state): string
     {
-        return json_encode((new ObjectMapperUsingReflection())->serializeObject($state));
+        return json_encode(
+            (new ObjectMapperUsingReflection())->serializeObject($state),
+            JSON_PRETTY_PRINT,
+        );
     }
 
     /** @internal */