diff --git a/ocurrent-plugin/connection.ml b/ocurrent-plugin/connection.ml
index 957d9efe..49a5ebcb 100644
--- a/ocurrent-plugin/connection.ml
+++ b/ocurrent-plugin/connection.ml
@@ -29,6 +29,13 @@ type t = {
   max_pipeline : int;
 }
 
+(* Replace this with the version in capnp-rpc 1.2, once released *)
+let await_settled_exn t =
+  Capability.wait_until_settled t >|= fun () ->
+  match Capability.problem t with
+  | None -> ()
+  | Some e -> Fmt.failwith "%a" Capnp_rpc.Exception.pp e
+
 (* Return a proxy to the scheduler, starting a new connection if we don't
    currently have a working one. *)
 let sched ~job t =
@@ -44,7 +51,7 @@ let sched ~job t =
       Lwt.catch
         (fun () ->
            Sturdy_ref.connect_exn conn.sr >>= fun cap ->
-           Capability.wait_until_settled cap >|= fun () ->
+           await_settled_exn cap >|= fun () ->
            cap
         )
         (fun ex ->
@@ -107,11 +114,11 @@ let submit ~job ~pool ~action ~cache_hint ?src ?secrets ~urgent t ~priority ~swi
                   let build_job = Cluster_api.Ticket.job ticket in
                   stage := `Get_ticket ticket;       (* Allow the user to cancel it now. *)
                   Prometheus.Gauge.inc_one Metrics.queue_get_ticket;
-                  Capability.wait_until_settled ticket >>= fun () ->
+                  await_settled_exn ticket >>= fun () ->
                   Prometheus.Gauge.dec_one Metrics.queue_get_ticket;
                   Current.Job.log job "Waiting for worker...";
                   Prometheus.Gauge.inc_one Metrics.queue_get_worker;
-                  Capability.wait_until_settled build_job >>= fun () ->
+                  await_settled_exn build_job >>= fun () ->
                   Prometheus.Gauge.dec_one Metrics.queue_get_worker;
                   Capability.dec_ref ticket;
                   stage := `Got_worker;