diff --git a/xo-gc/include/xo/gc/X1Collector.hpp b/xo-gc/include/xo/gc/X1Collector.hpp
index c9d00da3..38999844 100644
--- a/xo-gc/include/xo/gc/X1Collector.hpp
+++ b/xo-gc/include/xo/gc/X1Collector.hpp
@@ -7,5 +7,6 @@
 
 #include "DX1Collector.hpp"
 #include "detail/ICollector_DX1Collector.hpp"
+#include "detail/IAllocator_DX1Collector.hpp"
 
 /* end X1Collector.hpp */