diff --git a/src/tef-tldrs/trace_tef_tldrs.ml b/src/tef-tldrs/trace_tef_tldrs.ml
index 47584a4..bcd61b2 100644
--- a/src/tef-tldrs/trace_tef_tldrs.ml
+++ b/src/tef-tldrs/trace_tef_tldrs.ml
@@ -120,11 +120,22 @@ let collector ~out () : collector =
   | None -> assert false
   | Some c -> subscriber_ c |> Trace_subscriber.collector
 
+open struct
+  let register_atexit =
+    let has_registered = ref false in
+    fun () ->
+      if not !has_registered then (
+        has_registered := true;
+        at_exit Trace_core.shutdown
+      )
+end
+
 let setup ?(out = `Env) () =
   let role = find_role ~out () in
   match role with
   | None -> ()
   | Some c ->
+    register_atexit ();
     Trace_core.setup_collector @@ Trace_subscriber.collector @@ subscriber_ c
 
 let with_setup ?out () f =
diff --git a/src/tef/trace_tef.ml b/src/tef/trace_tef.ml
index e29488f..39b9c06 100644
--- a/src/tef/trace_tef.ml
+++ b/src/tef/trace_tef.ml
@@ -78,7 +78,18 @@ let[@inline] subscriber ~out () : Trace_subscriber.t =
 let[@inline] collector ~out () : collector =
   collector_ ~finally:ignore ~mode:`Single ~out ()
 
+open struct
+  let register_atexit =
+    let has_registered = ref false in
+    fun () ->
+      if not !has_registered then (
+        has_registered := true;
+        at_exit Trace_core.shutdown
+      )
+end
+
 let setup ?(out = `Env) () =
+  register_atexit ();
   match out with
   | `Stderr -> Trace_core.setup_collector @@ collector ~out:`Stderr ()
   | `Stdout -> Trace_core.setup_collector @@ collector ~out:`Stdout ()