0117 went a step further than it had grounds for. It was right that the bus
is the only bus, and wrong that the amqp interface must therefore retire —
because it conflated two reasons to want a broker. Using one to reach
another module is a second bus and stays refused. Needing an AMQP broker as
a backing service, the way something needs a database, is ordinary, and
forbidding it would make the mesh unable to run normal software while
calling that architecture.
So the broker becomes a plain provider module: no seat, not foundation,
never raised at genesis, no retirement condition. lavinmq now claims nothing
and provides amqp; nats claims mesh-broker and provides nothing.
The rule that survives is about direction, not software: inter-module
communication goes over the bus. A module may hold a broker for itself; it
may not use one as a channel to another module. That is a review judgement
where 0117 could have used a parser, which is the honest cost.
0106's progressive insight was itself wrong and is corrected by a second one
there — nothing moves off the old broker, so its "one purpose" sentence does
not become true, it is just not what that server is.
The insight check needed two fixes it found itself: a date may carry
trailing words, and a bold run with a link is discussing an insight rather
than marking one. All four bad shapes still fire.
A module does declare requirements the provisioner fulfils — but the broker
it gets that way is a private vhost, the analog of a database, not the
mesh's bus. Two modules of the new mesh depend on it, so the compatibility
broker was never single-purpose and its retirement would have stranded them.
NATS is the heart: one bus, a module's messaging is subjects on it scoped by
what it declares, and no module is handed a server of its own. The seat
delivers nothing; the interface retires with the broker. Also closes the
EVENTS question — one stream, on the bootstrap argument, not preference.
Designs 25 and 28 go in-progress: step 1 is starting.
The insight check caught a false positive on its own first real use — its
bold-run pattern crossed newlines and joined an unrelated `**` to the
marker. Constrained to one line, still catching all four bad shapes.
jschoubben