diff --git a/demo/sandbox.cpp b/demo/sandbox.cpp
index 9a13156..e9eeb8f 100644
--- a/demo/sandbox.cpp
+++ b/demo/sandbox.cpp
@@ -1,15 +1,19 @@
 #include "matador/object/schema.hpp"
 
+#include "matador/logger/log_manager.hpp"
+
 #include "author.hpp"
 #include "book.hpp"
 
 using namespace demo;
 using namespace matador;
 int main() {
-  object::schema tree;
+    logger::default_min_log_level(logger::log_level::LVL_DEBUG);
+    logger::add_log_sink(logger::create_stdout_sink());
 
+    object::schema schema;
 
-    tree.attach<author>("authors");
-    tree.attach<book>("books");
+    auto result = schema.attach<author>("authors")
+        .and_then([&schema] { return schema.attach<book>("books"); });
 
 }
\ No newline at end of file