The substrate's store and the postgres module are the same thing. They were two
rows only while the substrate was a different KIND of thing — a store raised from
a bundle cannot provide postgres-database, so anything wanting a database needed
a second server. It is visible on any mesh built today: mesh-store and postgres,
two containers, the same image.
Which name survives is settled by the naming rule. Where a consumer speaks a
protocol the interface is the protocol, and "database" is not a capability. The
control plane's own queries use distinct on and on conflict, so the coupling is
to postgres and a "store" module would advertise a swap that fails the first time
anyone tries it.
The broker collapses the same way with a different outcome: amqp IS a protocol
that several implementations speak, so amqp is a legitimate provision and lavinmq
is one provider of it.
So adopting the substrate is not only an upgrade path — it is two rows of a
mesh's module list becoming one, twice. And it leaves nothing that is a specialty
after the pivot, which is the claim the whole design rests on and is not true
today for exactly those two.
Claude-Session: https://claude.ai/code/session_01D6qtiYU3P9jk3pnAXyAFyx
jschoubben
87f464cc5f