outis: Fight AI spam by generating and sending a fake 'user unknown' bounce emails
Summary
Outis is a tool that fights spam by generating and sending a fake 'user unknown' bounce when an email is received, so the sender believes the recipient's address does not exist. It leverages RFC 3464 delivery status notifications modeled on Postfix, targeting the original Return-Path and using a controlled domain to improve credibility. The article covers usage, limitations, configuration details, and considerations with email providers that rewrite headers and suppression lists from providers like Amazon SES.