MailCue

What it does

MailCue is an all-in-one email testing server packaged in a single Docker container. Unlike simple catch-all SMTPs, it provides a fully-featured mail stack with Postfix, Dovecot, SpamAssassin, DKIM/DMARC verification, and a modern React UI. Test your email workflows exactly as they behave in production with IMAP/POP3 access, API injection, real-time events, and GPG encryption. Perfect for local development, CI/CD pipelines, and ensuring your transactional emails actually deliver.

A fully-featured email testing server in a single Docker container. SMTP, IMAP, DKIM, DMARC, SpamAssassin, a REST API with Python & Node SDKs, an MCP server for AI agents, and a modern web UI. Run it for tests or as a real production mail server.

A full mail stack in one Docker container: SMTP, IMAP, DKIM/DMARC, spam filtering, a REST API with Python & Node SDKs, and an MCP server for AI agents. Test email exactly as it behaves in production — or deploy it as a real mail server. One container replaces an entire email infrastructure. SQLite works out of the box, while PostgreSQL is available for larger production workloads. Accepts mail for any address on any domain. Nothing ever leaves the container. Safe by default. Full Dovecot server with STARTTLS and implicit TLS. Use Thunderbird, mutt, or any standard client. OpenDKIM signing, OpenDMARC verification, and SPF policy checks. Validate email authentication end-to-end.…from olib-ai.github.io

• AF
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• FS
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• PI
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