Open source

Burngate

An open-source SMTP gateway, written in Rust, that filters invalid recipients at RCPT TO using Redis — so disposable-email infrastructure stays fast and rejects junk before it ever hits your app.

• Rejects unknown recipients at the SMTP handshake (RCPT TO), before DATA
• Redis-backed address lookups for low-latency filtering
• Lightweight and fast — built in Rust
• Open source, MIT licensed