#smtp
4 posts
Postern is at v1.4.1. v1.4.0 bound read and send to a person, not a shared mailbox god-token; v1.4.1 fixes the webmail attachment-send race. Conrad Rockenhaus covers identity-bound registry credentials, MCP multi-person setup, the projection census that keeps IMAP honest, and what still stays estate-wide on purpose.
Postern tagged v1.0.0 on July 9, 2026: the first production-ready release of the self-hostable Cloudflare mailbox for humans and agents. Notes on what the tag means, the five-week path from send-only cf-email-relay to a full store with webmail and IMAP, the acceptance smoke that gates the release, and the honest cost of making real mail clients happy.
Postern replaces our retired send-only cf-email-relay with a full mailbox: inbound via Email Routing, outbound via Email Sending, D1 and R2 storage, FTS and optional semantic search, webmail and read-only IMAP, a Go SMTP relay for legacy callers, and one structured API that agents and humans both use.
A small two-part utility for sending transactional email through Cloudflare Email Sending: a Worker with a service-binding RPC and a token-gated HTTP endpoint, and a tiny Go SMTP relay that bridges the services that can only speak SMTP. Notes on the one-validation-path design, why the SMTP bridge is the genuinely useful part, the container wrinkle that made the relay multi-listen, and wiring Jenkins and Uptime Kuma to send through it.