Reframe after the user's insight, confirmed in code: artdag-on-sx already IS the substrate-
independent behavior engine — artdag/run injects the RUNNER (execution adapter: SX op-table /
Erlang / Celery), federation.sx injects the TRANSPORT (communication adapter: fed-sx / HTTP /
IPFS). Business logic = a content-addressed DAG; durability is a RUNNER capability (same DAG runs
eager or durable); deployment (subdomain service / peer / L1 worker) is placement. fed-sx+Erlang
is ONE adapter set, not the architecture. The type carries content-grammar + allowed-relations +
a behavior DAG. The prior fed-sx/Erlang framing is kept as one concrete first slice.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>