diff --git a/spiner/regular_grid_1d.hpp b/spiner/regular_grid_1d.hpp
index 6753d8fbb..b76a404b3 100644
--- a/spiner/regular_grid_1d.hpp
+++ b/spiner/regular_grid_1d.hpp
@@ -31,6 +31,7 @@
 #include "ports-of-call/portable_errors.hpp"
 #include "sp5.hpp"
 #include "spiner_types.hpp"
+#include "transformations.hpp"
 
 namespace Spiner {