Run as a fully hardened production email server.
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.
MailCue provides a modern React-based web UI with mailbox navigation, rich email viewer, and HTML compose editor. Developers can visually inspect received emails, view headers, and test email rendering without leaving the local environment.
MailCue includes automatic DKIM signing, DMARC verification, GPG/PGP-MIME support, and SpamAssassin spam filtering. Teams can test email authentication flows end-to-end and validate that security headers and encryption work correctly before production deployment.
MailCue exposes a comprehensive REST API with JSON endpoints for sending, receiving, searching, and managing emails. This enables developers to programmatically inject test emails, verify delivery, and validate email behavior as part of automated test suites.
MailCue provides a complete mail server in a single Docker container with SMTP, IMAP, DKIM, DMARC, and spam filtering. Developers can spin up a realistic email environment locally in 30 seconds with no external databases or configuration, enabling end-to-end email testing in development workflows.