diff --git a/src/Reactor/Nucleus.hpp b/src/Reactor/Nucleus.hpp
index a552b41..6414780 100644
--- a/src/Reactor/Nucleus.hpp
+++ b/src/Reactor/Nucleus.hpp
@@ -73,7 +73,7 @@
 		{
 			#if defined(REACTOR_DEFAULT_OPT_LEVEL)
 			{
-				level = Level::REACTOR_DEFAULT_OPT_LEVEL;
+				this->level = Level::REACTOR_DEFAULT_OPT_LEVEL;
 			}
 			#endif
 		}