diff --git a/nix/host-modules/swarm-required-services.nix b/nix/host-modules/swarm-required-services.nix
index 94d82ba3..4035ce81 100644
--- a/nix/host-modules/swarm-required-services.nix
+++ b/nix/host-modules/swarm-required-services.nix
@@ -47,5 +47,16 @@ in
   config.services.hyperhive.swarm = {
     matrix.enable = lib.mkDefault swarmCfg.enableRequiredServices;
     authelia.enable = lib.mkDefault swarmCfg.enableRequiredServices;
+    # The queue. Added later than the two above and missed at the time —
+    # this file predates the `swarm-nats` container by nine days and had
+    # not been revisited since, so its absence was sequence rather than
+    # intent. It meets the rule in the option's own description exactly:
+    # once per swarm, and optional.
+    #
+    # The tell that it was an omission: `local-defaults.nix` already
+    # derives `nats.autoGenerateCallout` from the all-local mode, so that
+    # mode was minting the queue's callout nkeys and then never starting
+    # the queue they authenticate against.
+    nats.enable = lib.mkDefault swarmCfg.enableRequiredServices;
   };
 }