**Stalwart Mail Server** is an open-source mail server solution with JMAP, IMAP4, and SMTP support and a wide range of modern features. It is written in Rust and designed to be secure, fast, robust and scalable.
- Built-in [DMARC](https://datatracker.ietf.org/doc/html/rfc7489), [DKIM](https://datatracker.ietf.org/doc/html/rfc6376), [SPF](https://datatracker.ietf.org/doc/html/rfc7208) and [ARC](https://datatracker.ietf.org/doc/html/rfc8617) support for message authentication.
- Strong transport security through [DANE](https://datatracker.ietf.org/doc/html/rfc6698), [MTA-STS](https://datatracker.ietf.org/doc/html/rfc8461) and [SMTP TLS](https://datatracker.ietf.org/doc/html/rfc8460) reporting.
- Inbound throttling and filtering with granular configuration rules and Sieve scripting.
- Virtual queues with delayed delivery, priority delivery, quotas, routing rules and throttling support.
- **Flexible**:
- **LDAP** directory and **SQL** database authentication.
- Full-text search available in 17 languages.
- Disk quotas.
- Sieve scripting language with support for all [registered extensions](https://www.iana.org/assignments/sieve-extensions/sieve-extensions.xhtml).
- Subaddressing and catch-all addresses support.
- Integration with **OpenTelemetry** to enable monitoring, tracing, and performance analysis.
- **Secure**:
- OAuth 2.0 [authorization code](https://www.rfc-editor.org/rfc/rfc8628) and [device authorization](https://www.rfc-editor.org/rfc/rfc8628) flows.
- Access Control Lists (ACLs).
- Rate limiting.
- **Robust and scalable**:
- **FoundationDB** or **SQLite** database backends.
If you are having problems running Stalwart Mail Server, you found a bug or just have a question,
do not hesitate to reach us on [Github Discussions](https://github.com/stalwartlabs/mail-server/discussions),
[Reddit](https://www.reddit.com/r/stalwartlabs) or [Discord](https://discord.gg/aVQr3jF8jd).
Additionally you may become a sponsor to obtain priority support from Stalwart Labs Ltd.
## Funding
Part of the development of this project was funded through the [NGI0 Entrust Fund](https://nlnet.nl/entrust), a fund established by [NLnet](https://nlnet.nl/) with financial support from the European Commission's [Next Generation Internet](https://ngi.eu/) programme, under the aegis of DG Communications Networks, Content and Technology under grant agreement No 101069594.
If you find the project useful you can help by [becoming a sponsor](https://github.com/sponsors/stalwartlabs). Thank you!