diff --git a/libs/util/include/psemek/util/ecs.hpp b/libs/util/include/psemek/util/ecs.hpp
index 617b536a..3ad11836 100644
--- a/libs/util/include/psemek/util/ecs.hpp
+++ b/libs/util/include/psemek/util/ecs.hpp
@@ -142,6 +142,8 @@ namespace psemek::util
 
 				((std::get<Components *>(ctx.components) = get_species_component<Components>()), ...);
 
+				behavior.begin({id_}, *std::get<Components *>(ctx.components)...);
+
 				auto visit = [&](auto * ... ptrs)
 				{
 					if constexpr (std::is_invocable_v<Behavior, typename Components::data & ..., typename Behavior::context const &, Args const & ...>)
@@ -441,6 +443,8 @@ namespace psemek::util
 					return *std::get<Component *>(components);
 				}
 			};
+
+			void begin(species_handle, Components const & ...) {}
 		};
 
 		enum class policy