research: Mode B on Cloudflare — operational receipts from an outside operator

[NorthwoodsSentinel]

Summary

Field notes contribution from an operator who has been running The Rhizome — a fleet of substrate-sovereign instances on per-member Cloudflare accounts — since mid-2025. Contributed against the-metafactory/cortex#1189 (Mode B isolated stack hosting, pre-release federation track) and the "Joining a Network — Sovereign Model B Federation" infographic Andreas shared in #cortex on 2026-06-26.

Frame

Not a vendor pitch. The doc explicitly honors @mellanon's 2026-06-15 vendor-agnostic principle ("choice is an important aspect of a vendor agnostic platform") — CF is offered as ONE reference recipe alongside hypothetical recipes for AWS, GCP, self-hosted, etc., authored by operators with shipping experience on each.

§1 names the composition explicitly: this contribution is the substrate-axis half of the convergence already documented in PR #111 — the 2026-06-07 Rhizome ↔ stack interface map. Cortex is formalizing the M7 head shape; The Rhizome has been operationally running what Mode B's substrate floor looks like in production. The CF Mode B recipe is the merger of the two architectures on the substrate axis.

Substantive content

• §3 layer mapping of cortex Mode B daemon onto CF primitives (Workers, Durable Objects, R2, D1, KV, AI Gateway, Pages)
• §4 the NATS-on-CF gap with three operational options — cloudflared TCP tunnel, JC's public hub dial-out (already in docs/runbook-federation-peering.md), CF-native federation transport
• §5 the 5-step join from the infographic (Provision → Register → Pin → Admission → Verify) mapped to one wrangler deploy + minimal config, noting that cortex#1232's default registry trust anchor (merged 2026-06-26) already eliminates the "Pin" step
• §6 install-pain receipts from a real 2026-06-26 cortex install (community arc registry 404, agents/CREATING.md grove dead-end, PI-001 content-filter false positive)
• §7 compositions with @mellanon's soma and Meridian
• §8 concrete next-step authorship offers (cortex-stack-cf-template Spike B1 candidate, install log, NATS-on-CF design doc)

Composes with

• PR research: Rhizome ↔ myelin + cortex + soma — an interface map #111 (mellanon/pai-collab) — the architectural-comparison prior art the §1 framing depends on, pending review since 2026-06-14
• the-metafactory/cortex PR #1189 — the Mode A + Mode B design split this contributes against
• the-metafactory/cortex src/runner/execution-backend.ts:33 — the existing cloudflare placeholder

Co-authored-by: Margin margin@northwoodssentinel.com