Zero-Config Decoy Sender Registry

Who it's for

Small-to-medium business IT admins who currently rely on standard SPF/DKIM filters that miss complex lookalike domains.

The problem

High risk of financial loss and credential theft due to sophisticated lookalike domain phishing that exploits poor brand infrastructure.

How to build it

A lightweight DNS-queried registry API with integrations for popular open-source mail filters (Rspamd, SpamAssassin) and a visual reporting dashboard.

Why it doesn't exist yet

Major shipping and courier brands have legacy infrastructures that make rotating valid domains slow, while previous anti-phishing networks relied on slow, manual reporting databases rather than low-latency DNS query propagation.

First users

Independent IT administrators managing custom mailservers who need an immediate, zero-maintenance defense against specific lookalike shipping domains.

Build size

2 people x 8 weeks

Biggest risk

Aggressive blocking of lookalike domains may result in false positives for legitimate marketing subdomains if shipping entities use inconsistent naming conventions.

Conditions for a hit (all 3 required)

• A real-time DNS-based query service responding to sender checks in under 50ms.
• An open-source integration plugin for Rspamd and SpamAssassin that automatically assigns a spam weight based on lookalike scoring.
• A web-based verification interface allowing users to upload .eml headers to trace and flag spoofed routing jumps.

How it's judged (in 6 months)

GitHub repository for the Rspamd/SpamAssassin integration reaching 250 stars and listed in Product Hunt weekly top 10.(judgment date 2027-02-06)

AI self-confidence 72/100 — self-reported likelihood of meeting the criterion, not a business success rate