diff --git a/include/reactor-cpp/graph.hh b/include/reactor-cpp/graph.hh
old mode 100644
new mode 100755
index 54b8034b..382bc596
--- a/include/reactor-cpp/graph.hh
+++ b/include/reactor-cpp/graph.hh
@@ -14,6 +14,7 @@
 #include <optional>
 #include <type_traits>
 #include <vector>
+#include <algorithm>
 
 namespace reactor {
 class GraphElement {
@@ -309,4 +310,4 @@ public:
   }
 };
 } // namespace reactor
-#endif // REACTOR_CPP_GRAPH_HH
\ No newline at end of file
+#endif // REACTOR_CPP_GRAPH_HH