diff --git a/debug/debugger.hpp b/debug/debugger.hpp
index 7f43a369..b4d9c4e2 100644
--- a/debug/debugger.hpp
+++ b/debug/debugger.hpp
@@ -1,3 +1,5 @@
+#pragma once
+
 void breakpoint (void);
 void await_debugger (void);
 void prepare_debugger (void);