diff --git a/debug.hpp b/debug.hpp
index 6a97adad..ea38db49 100644
--- a/debug.hpp
+++ b/debug.hpp
@@ -22,6 +22,7 @@
 
 
 #include "annotations.hpp"
+#include "maths.hpp"
 
 #include <stdexcept>
 #include <iostream>