The complete recipe, found across five runs: adopt BOTH the store (postgres) and broker
(lavinmq) on the control-node — the broker's `listens` is what opens 5671 in the firewall
for cross-node bus access; deliver the store's genesis superuser via `secret accept` (else
the module mints a random one that cannot log in to the running store); inject the provider
seal key (open hq issue 022 workaround); push the provider node again after the remote
consumers (issue 057); and tolerate provisioner-runtime startup churn — a cross-node
provisioner exits until the overlay tunnel is up, then settles. baserow and letta on the
joined node get their databases from the one foundation store over the overlay.
https://claude.ai/code/session_01D6qtiYU3P9jk3pnAXyAFyx