diff --git a/include/sdbusplus/async/callback.hpp b/include/sdbusplus/async/callback.hpp
index 61596c4..61efab8 100644
--- a/include/sdbusplus/async/callback.hpp
+++ b/include/sdbusplus/async/callback.hpp
@@ -132,6 +132,8 @@
 template <takes_msg_handler Init>
 struct callback_sender
 {
+    using is_sender = void;
+
     explicit callback_sender(Init init) : init(std::move(init)){};
 
     // This Sender yields a message_t.
diff --git a/include/sdbusplus/async/match.hpp b/include/sdbusplus/async/match.hpp
index b193a50..40ecbe5 100644
--- a/include/sdbusplus/async/match.hpp
+++ b/include/sdbusplus/async/match.hpp
@@ -122,6 +122,8 @@
 // match Sender implementation.
 struct match_sender
 {
+    using is_sender = void;
+
     match_sender() = delete;
     explicit match_sender(match& m) noexcept : m(m){};
 
diff --git a/include/sdbusplus/async/timer.hpp b/include/sdbusplus/async/timer.hpp
index de54b97..699265a 100644
--- a/include/sdbusplus/async/timer.hpp
+++ b/include/sdbusplus/async/timer.hpp
@@ -78,6 +78,8 @@
  */
 struct sleep_sender : public details::context_friend
 {
+    using is_sender = void;
+
     sleep_sender() = delete;
 
     sleep_sender(context& ctx, event_t::time_resolution time) noexcept :
diff --git a/src/async/context.cpp b/src/async/context.cpp
index c8f7e5f..5a5bc8c 100644
--- a/src/async/context.cpp
+++ b/src/async/context.cpp
@@ -84,6 +84,8 @@
 /* The sender for the wait/process event. */
 struct wait_process_sender
 {
+    using is_sender = void;
+
     explicit wait_process_sender(context& ctx) : ctx(ctx) {}
 
     friend auto tag_invoke(execution::get_completion_signatures_t,