celery-sx = one more runner on artdag/op-table-runner, not a Celery port: broker=persist KV,
workers=er-scheduler, result backend=content-addressed (dedup free), retries/replay=flow-on-
erlang, fan-out=artdag/schedule. ~few hundred lines of glue, zero packages, 'Celery the way it
should have been' on erlang-on-sx. DEMAND-DRIVEN (RX) — build when a DAG needs heavy compute /
long-running-retryable / cross-machine fan-out; the synchronous op-table runner covers P0.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>