dmarc

OpenOSINT

+36

Open-source engine for passive OSINT checks: 21 tools as CLI, MCP server and web UI. Hosted Monitor & Diligence at app.openosint.tech.

Mailu/Mailu

+15

Insular email distribution - mail server as Docker images

foxcpp/maddy

+5

✉️ Composable all-in-one mail server.

retlehs/quien

+5

A better whois and domain intelligence toolkit

parsedmarc

+3

A Python package and CLI for parsing aggregate and forensic DMARC reports

awesome-opensource-email

+2

Awesome Opensource Email Resources

sentio

+1

Email inbox API for AI agents. Give every agent its own real email address, receive mail as structured webhooks, and reply in-thread over REST. A complete multi-tenant mail server in Rust: inbound and outbound, DKIM/SPF/DMARC/ARC, MTA-STS, DANE, three-tier anti-spam.