diff --git a/headers/ecs.hpp/ecs.hpp b/headers/ecs.hpp/ecs.hpp
index b0738bb..c2dfec7 100644
--- a/headers/ecs.hpp/ecs.hpp
+++ b/headers/ecs.hpp/ecs.hpp
@@ -1914,7 +1914,7 @@ namespace ecs_hpp
         auto applier = std::make_unique<applier_t>(
             std::make_tuple(std::forward<Args>(args)...));
         const auto family = detail::type_family<T>::id();
-        appliers_.emplace(family, std::move(applier));
+        appliers_.insert_or_assign(family, std::move(applier));
         return *this;
     }
 
diff --git a/untests/ecs_tests.cpp b/untests/ecs_tests.cpp
index c32e5c5..8fd31c5 100644
--- a/untests/ecs_tests.cpp
+++ b/untests/ecs_tests.cpp
@@ -586,6 +586,15 @@ TEST_CASE("registry") {
             REQUIRE(e2.component_count() == 1u);
             REQUIRE(e2.get_component<position_c>() == position_c(1,2));
         }
+        {
+            ecs::prototype p;
+            p.component<position_c>(1, 2);
+            p.component<position_c>(11, 22);
+
+            ecs::registry w;
+            const auto e1 = w.create_entity(p);
+            REQUIRE(e1.get_component<position_c>() == position_c(11,22));
+        }
         {
             const auto p = ecs::prototype()
                 .component<position_c>(1,2)