Cloudflare Email Relay

The Cloudflare Email Relay is the inbound half of Avunu's Cloudflare Email suite. Cloudflare Email Routing hands each message to this Worker, which stores it and pushes it to the ERP that owns the recipient's domain: an Odoo database running mail_cloudflare or a Frappe site running cloudflare_email_delivery. An ERP outage, a wrong secret, or a bad deploy can delay a message, but it can't lose one. It's for teams running several ERP instances on Cloudflare-hosted domains who want to drop IMAP mailboxes entirely.

Features

• Store first. Each message is written to R2 before anything else happens. If storage fails, Cloudflare tells the sending server to retry.

• Durable delivery. One SQLite-backed Durable Object per tenant delivers messages oldest first, with back-off and retention you can tune.

• Signed pushes. Every attempt is an HTTPS POST of the raw message, signed with HMAC-SHA256 and timestamped. Optional Cloudflare Access service tokens are supported.

• Multi-tenant. One Worker serves many ERP instances, routed by recipient domain, including wildcard subdomains. Unknown or disabled domains are rejected at SMTP time.

• Ops API per tenant, behind a bearer token, to list, inspect, retry, and delete deliveries.

• Library, not app. Deployments are thin wrappers with a tenant table, and the same validation schemas run in CI.

Getting started

The relay is published as an npm package. A deployment is a few lines of wrapper code, a tenants.json, and a wrangler.jsonc, and it needs the Workers Paid plan. The README documents the tenant model, the inbound contract, and deployment. Pair it with the Frappe or Odoo adapter.