diff --git a/config/default.yml b/config/default.yml
index 798d8e0..2ff9448 100644
--- a/config/default.yml
+++ b/config/default.yml
@@ -63,11 +63,22 @@ network:
 
   node_id: "ret000000000"
 
-  # Forward detections to external tracker container
+  # Forward detections to the retina-tracker sidecar. blah2_api enriches each
+  # frame with ADS-B truth before forwarding, so the tracker gets the annotated
+  # frame rather than the bare one, which is where a track's adsb_hex comes from.
+  #
+  # 127.0.0.1 rather than a container name: retina-tracker runs with
+  # network_mode host and binds loopback only (--tcp-host 127.0.0.1), and
+  # blah2_api is on the same host network. The default 'blah2_tracker:3012'
+  # names a container from blah2's own compose, which does not exist here.
+  #
+  # This must stay in step with retina-gui: the tracker's ingest socket accepts
+  # one connection at a time, so exactly one process may feed it. retina-gui
+  # stopped forwarding in the same release that turned this on.
   tracker_forward:
-    enabled: false
-    host: 'blah2_tracker'
-    port: 3012
+    enabled: true
+    host: '127.0.0.1'
+    port: 30100
 
 truth:
   adsb:
diff --git a/docker-compose.yml b/docker-compose.yml
index eb369b8..3093d42 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -176,11 +176,17 @@ services:
         condition: service_completed_successfully
     # --tcp-host 127.0.0.1 (not the image's 0.0.0.0 default): network_mode
     # host means 0.0.0.0 would bind the real host interface, exposing the
-    # ingest port to the LAN. retina-gui is always colocated on this same
-    # host, so loopback-only is sufficient.
+    # ingest port to the LAN. blah2_api (which feeds it) and retina-gui (which
+    # controls it) are both colocated on this same host, so loopback-only is
+    # sufficient for both ports.
+    #
+    # --control-port carries POST /reset and GET /health. Auto-Calibrate needs
+    # the reset between candidate towers, and it cannot ride the ingest socket
+    # any more: that accepts one connection at a time and blah2_api owns it.
     command: >
       python -m retina_tracker.track_detections
       --tcp --tcp-host 127.0.0.1 --tcp-port 30100
+      --control-host 127.0.0.1 --control-port 30101
       -s /app/output/events.jsonl
       -c /config/retina-tracker.yaml
       --blah2-config /config/config.yml