diff --git a/solanaceae/message3/registry_message_model.hpp b/solanaceae/message3/registry_message_model.hpp
index cec5e0b..fe3d49c 100644
--- a/solanaceae/message3/registry_message_model.hpp
+++ b/solanaceae/message3/registry_message_model.hpp
@@ -69,6 +69,9 @@ struct RegistryMessageModelEventI : public MessageModel3I {
 using RegistryMessageModelEventProviderI = EventProviderI<RegistryMessageModelEventI>;
 
 class RegistryMessageModel : public RegistryMessageModelEventProviderI, public MessageModel3I {
+	public:
+		static constexpr const char* version {"1"};
+
 	protected:
 		Contact3Registry& _cr;