diff --git a/crates/core/tedge_actors/src/actors.rs b/crates/core/tedge_actors/src/actors.rs
index 1922ffab99c..37cd56afaa5 100644
--- a/crates/core/tedge_actors/src/actors.rs
+++ b/crates/core/tedge_actors/src/actors.rs
@@ -78,6 +78,7 @@ pub mod tests {
     async fn running_an_actor_without_a_runtime() {
         let mut box_builder = SimpleMessageBoxBuilder::new("test", 16);
         let mut client_message_box = box_builder.new_client_box(NoConfig);
+        let mut runtime_box = box_builder.get_signal_sender();
         let actor_message_box = box_builder.build();
         let actor = Echo {
             messages: actor_message_box,
@@ -93,7 +94,10 @@ pub mod tests {
         assert_eq!(client_message_box.recv().await, Some("World".to_string()));
 
         // When there is no more input message senders
-        client_message_box.close_sender();
+        runtime_box
+            .send(RuntimeRequest::Shutdown)
+            .await
+            .expect("fail to shutdown");
 
         // The actor stops
         actor_task
diff --git a/crates/core/tedge_actors/src/channels.rs b/crates/core/tedge_actors/src/channels.rs
index 0f6fe6f99ee..66f4f8eca1b 100644
--- a/crates/core/tedge_actors/src/channels.rs
+++ b/crates/core/tedge_actors/src/channels.rs
@@ -19,9 +19,6 @@ pub trait Sender<M>: 'static + Send + Sync {
 
     /// Clone this sender in order to send messages to the same receiver from another actor
     fn sender_clone(&self) -> DynSender<M>;
-
-    /// Closes this channel from the sender side, preventing any new messages.
-    fn close_sender(&mut self);
 }
 
 impl<M: Message> Clone for DynSender<M> {
@@ -46,10 +43,6 @@ impl<M: Message, N: Message + Into<M>> Sender<N> for mpsc::Sender<M> {
     fn sender_clone(&self) -> DynSender<N> {
         Box::new(self.clone())
     }
-
-    fn close_sender(&mut self) {
-        self.close_channel();
-    }
 }
 
 /// Make a `DynSender<N>` from a `DynSender<M>`
@@ -77,10 +70,6 @@ impl<M: Message, N: Message + Into<M>> Sender<N> for DynSender<M> {
     fn sender_clone(&self) -> DynSender<N> {
         Box::new(self.as_ref().sender_clone())
     }
-
-    fn close_sender(&mut self) {
-        self.as_mut().close_sender()
-    }
 }
 
 /// A sender that discards messages instead of sending them
@@ -95,8 +84,6 @@ impl<M: Message> Sender<M> for NullSender {
     fn sender_clone(&self) -> DynSender<M> {
         Box::new(NullSender)
     }
-
-    fn close_sender(&mut self) {}
 }
 
 impl<M: Message> From<NullSender> for DynSender<M> {
@@ -142,10 +129,6 @@ where
             cast: self.cast.clone(),
         })
     }
-
-    fn close_sender(&mut self) {
-        self.inner.as_mut().close_sender()
-    }
 }
 
 impl<M, N, NS, F> From<MappingSender<F, N>> for DynSender<M>
diff --git a/crates/core/tedge_actors/src/message_boxes.rs b/crates/core/tedge_actors/src/message_boxes.rs
index 38d386a2488..c604b451e5c 100644
--- a/crates/core/tedge_actors/src/message_boxes.rs
+++ b/crates/core/tedge_actors/src/message_boxes.rs
@@ -240,10 +240,6 @@ impl<Output: Debug + Send + Sync + 'static> Sender<Output> for LoggingSender<Out
             sender: self.sender.clone(),
         })
     }
-
-    fn close_sender(&mut self) {
-        Sender::<Output>::close_sender(&mut self.sender)
-    }
 }
 
 pub fn log_message_sent<I: Debug>(target: &str, message: I) {
@@ -320,10 +316,6 @@ impl<Input: Message, Output: Message> Sender<Output> for SimpleMessageBox<Input,
     fn sender_clone(&self) -> DynSender<Output> {
         self.output_sender.sender_clone()
     }
-
-    fn close_sender(&mut self) {
-        self.output_sender.close_sender()
-    }
 }
 
 pub struct CombinedReceiver<Input> {
diff --git a/crates/core/tedge_actors/src/servers/keyed_messages.rs b/crates/core/tedge_actors/src/servers/keyed_messages.rs
index f366d2a62df..bdab5493908 100644
--- a/crates/core/tedge_actors/src/servers/keyed_messages.rs
+++ b/crates/core/tedge_actors/src/servers/keyed_messages.rs
@@ -29,10 +29,6 @@ impl<K: Message + Clone, M: Message> Sender<M> for KeyedSender<K, M> {
             sender: self.sender.clone(),
         })
     }
-
-    fn close_sender(&mut self) {
-        self.sender.close_channel()
-    }
 }
 
 /// A vector of senders addressed using a sender id attached to each message
@@ -60,10 +56,4 @@ impl<M: Message> Sender<(usize, M)> for SenderVec<M> {
         let senders = self.senders.iter().map(|r| r.sender_clone()).collect();
         Box::new(SenderVec { senders })
     }
-
-    fn close_sender(&mut self) {
-        self.senders
-            .iter_mut()
-            .for_each(|s| s.as_mut().close_sender())
-    }
 }
diff --git a/crates/core/tedge_actors/src/test_helpers.rs b/crates/core/tedge_actors/src/test_helpers.rs
index 69857732c5b..5d2c289ea8c 100644
--- a/crates/core/tedge_actors/src/test_helpers.rs
+++ b/crates/core/tedge_actors/src/test_helpers.rs
@@ -362,10 +362,6 @@ where
     fn sender_clone(&self) -> DynSender<M> {
         self.inner.sender_clone()
     }
-
-    fn close_sender(&mut self) {
-        self.inner.close_sender()
-    }
 }
 
 impl<T> AsRef<T> for TimedMessageBox<T> {
diff --git a/crates/extensions/c8y_mapper_ext/src/tests.rs b/crates/extensions/c8y_mapper_ext/src/tests.rs
index 34a9fddf2a2..bf9a3f62094 100644
--- a/crates/extensions/c8y_mapper_ext/src/tests.rs
+++ b/crates/extensions/c8y_mapper_ext/src/tests.rs
@@ -2210,8 +2210,6 @@ async fn inventory_registers_unknown_entity_once() {
         mqtt.send(measurement_message.clone()).await.unwrap();
     }
 
-    mqtt.close_sender();
-
     let mut messages = vec![];
     while let Some(WrappedInput::Message(msg)) = mqtt.recv_message().await {
         messages.push(msg);
diff --git a/crates/extensions/tedge_timer_ext/src/builder.rs b/crates/extensions/tedge_timer_ext/src/builder.rs
index 9b7e8c4832a..72b8c9bd21e 100644
--- a/crates/extensions/tedge_timer_ext/src/builder.rs
+++ b/crates/extensions/tedge_timer_ext/src/builder.rs
@@ -86,10 +86,6 @@ impl<T: Message> Sender<Timeout<AnyPayload>> for TimeoutSender<T> {
             inner: self.inner.sender_clone(),
         })
     }
-
-    fn close_sender(&mut self) {
-        self.inner.as_mut().close_sender()
-    }
 }
 
 /// A Sender that translates timeout requests on the wire
@@ -113,8 +109,4 @@ impl<T: Message> Sender<SetTimeout<T>> for SetTimeoutSender {
             inner: self.inner.sender_clone(),
         })
     }
-
-    fn close_sender(&mut self) {
-        self.inner.as_mut().close_sender()
-    }
 }
diff --git a/crates/extensions/tedge_timer_ext/src/tests.rs b/crates/extensions/tedge_timer_ext/src/tests.rs
index 20faa1a25fa..cff8d95fae5 100644
--- a/crates/extensions/tedge_timer_ext/src/tests.rs
+++ b/crates/extensions/tedge_timer_ext/src/tests.rs
@@ -108,6 +108,7 @@ async fn should_shutdown_even_if_there_are_pending_timers() {
 #[tokio::test]
 async fn should_process_all_pending_timers_on_end_of_inputs() {
     let mut client_box_builder = SimpleMessageBoxBuilder::new("Test timers", 16);
+    let mut runtime_box = client_box_builder.get_signal_sender();
     let _ = spawn_timer_actor(&mut client_box_builder).await;
     let mut client_box = client_box_builder.build();
 
@@ -129,7 +130,10 @@ async fn should_process_all_pending_timers_on_end_of_inputs() {
         .unwrap();
 
     // Then close the stream of requests
-    client_box.close_sender();
+    runtime_box
+        .send(RuntimeRequest::Shutdown)
+        .await
+        .expect("fail to shutdown");
 
     // The actor timer is expected to shutdown,
     // but *only* after all the pending requests have been processed.