diff --git a/nix/host-modules/swarm-ui.nix b/nix/host-modules/swarm-ui.nix
index 3478c1b8..d5ed39e1 100644
--- a/nix/host-modules/swarm-ui.nix
+++ b/nix/host-modules/swarm-ui.nix
@@ -232,6 +232,10 @@ in
               auth_request_set $authelia_user $upstream_http_remote_user;
               proxy_set_header Remote-User $authelia_user;
               proxy_set_header Authorization "";
+              # The SSE streams (terminal, agent state, subagent terminal)
+              # must not sit in nginx's buffer. The controller's 15s
+              # keep-alive keeps them under nginx's 60s default read timeout.
+              proxy_buffering off;
             '';
           };
           "@swarm_api_unauthorized".extraConfig = ''