mailcow

mailcow is an open-source Docker-based groupware and email suite built from established components including Postfix, Dovecot, Rspamd, SOGo, Redis, MariaDB, Nginx, and Unbound. Its main advantage is a modern admin UI around a full mail-server stack.

At an early stage the deciding factors are what the free tier actually covers, what the first paid invoice looks like, and how much of a founding engineer's week the setup costs. Feature depth that only matters at a million sends a month is noise until it is not.

Against a waitlist, a launch announcement, onboarding email, and the first transactional sends, mailcow covers developer experience, and does not cover scheduling, SDK breadth, and webhook coverage. Whether that gap matters depends on how central those are to the build.

• Free tier: Free self-hosted, GPL-3.0
• Best published rate per 1,000: Tiers not published in comparable form
• Starts at: Free self-hosted
• DX score: 7/10
• Deliverability: Self-hosted deliverability depends on DNS, IP history, spam controls, and operator discipline. mailcow bundles Rspamd, DKIM support, quarantine controls, and administration UI around the stack.
• Operating since: Not published
• Scheduling: No
• SDKs: None
• Webhooks: No

Self-hosted deliverability depends on DNS, IP history, spam controls, and operator discipline. mailcow bundles Rspamd, DKIM support, quarantine controls, and administration UI around the stack.

Teams that want to self-host a full email and groupware suite.

Small product teams trying to avoid mail-server operations.