Posthorn
Communication & EmailA unified outbound mail gateway that lets self‑hosted applications forward transactional emails through a single provider (Postmark, Resend, Mailgun, AWS SES or an SMTP relay).
Features
- Three ingress methods: HTTP form, HTTP API, and SMTP listener.
- Five transport back‑ends: Postmark, Resend, Mailgun, AWS SES, outbound‑SMTP relay.
- Single Go binary deployment with TOML configuration.
- Built‑in honeypot, referer validation, rate limiting, and optional CSRF for form endpoints.
- Idempotent retry handling and per‑request “to_override” support for API mode.
Recent releases
View all 1 releases →Weekly OSS security release digest.
The CVE patches and breaking changes that affected production tools this week. One email, every Sunday.
No spam, unsubscribe anytime.
Install & Platforms
Install via
docker
Platforms
linux
arm64
Alternative to
Stalwart
Mailcow
iRedMail
Postal
Hyvor Relay
Listmonk