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>
Three framing fixes after review: (1) the event source is object-level state changes, NOT just
CID deltas — relations write edge:* rows so they don't shift the CID; content/status → Create/
Update, relations → Add/Remove (ActivityPub-faithful). (2) verbs are TRANSITIONS (on-publish =
draft→published, fire-once, not every delta of a published post). (3) the hybrid flow split is by
DURABILITY not complexity — the execute-fold is eager/synchronous (no wait); suspend/timer/human
flows are the Erlang escape hatch. Plus: effects-as-data need a DRIVER (host, for P0); P0.2 must
gate on the transition + run in the handler body (VmSuspended/er-scheduler risk); P0.3 gets an
acceptance criterion; P3 flags the fed-sx delivery M2 blocker + the deferred actor model.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Business logic as federated composition-flows (plans/business-logic-fed-flows.md). P0.1: the
host describes a published post as a fed-sx activity — host/blog--publish-activity(slug) →
{:type "create" :actor "site" :id <CID> :object {:type "article" :slug :category}} — the
exact shape next/'s trigger machinery consumes (verified: next/tests/triggers_e2e.sh 10/10).
category (drives the flow branch: newsletter suspends / urgent fires / else skip) comes from
the "category" field-value, else the first tag, else "urgent". + host/blog--post-category.
Design decided: activity log = every CID delta (event source); triggers = declared subscriptions
(DefineTrigger); flows hybrid (SX composition for simple via the execute-fold, named Erlang flows
for complex); federated execution = Erlang (next/); the type carries content+relations+behavior.
blog 200/200 (+3: contract, category fallback, missing-post nil).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
