diff --git a/runtime/main.rb b/runtime/main.rb
index 4d423dd..e74529d 100644
--- a/runtime/main.rb
+++ b/runtime/main.rb
@@ -12,6 +12,8 @@ end
 def main(argv)
   init_loadpath
   load_lib_files
+  window = Window.new
+  Window.event_loop
 end
 
 main(ARGV)