Hosts

A host owns the process for one transport: it opens the listener or consumer, opens a demesne fork scope per invocation, runs the handler through the kernel's runHandler, and maps the outcome to the transport's vocabulary through a total DispositionMap.

Hosts contain no DI, lifecycle, validation, or dispatch logic of their own — that all lives in the kernel, once. A host is pure transport glue.

Host	Transport	Disposition D	Invocation unit
@btravstack/start-api	HTTP (Hono)	HTTP status	per request
@btravstack/start-amqp	AMQP / RabbitMQ	ack / requeue / dead-letter	per message
@btravstack/start-temporal	Temporal	retryable / non-retryable	per activity

HTTP — @btravstack/start-api

createHttpApp + httpListener: contracts become routes, handler outcomes become statuses. The listener owns startup and graceful shutdown of the Node server.

AMQP — @btravstack/start-amqp

Settlement dispositions (ack, requeue, dead-letter) over a wire AmqpDriver, with an optional IdempotencyStore for redelivery — a message seen twice runs the use case once.

Temporal — @btravstack/start-temporal

Activities as demesne-wired use cases. Determinism is enforced structurally: workflows receive activity proxies, never a container, so a workflow cannot accidentally reach non-deterministic code.