JMAP Server

Open-source JSON Meta Application Protocol server designed to be secure, fast, robust and scalable.

Key features

Full JMAP support

Supports JMAP Core, JMAP Mail, JMAP over WebSocket and JMAP for Sieve Scripts.

Flexible and robust

Full-text search, Quota support, Sieve filtering, OAuth and more.

Powered by Rust

Incredibly fast while ensuring memory safety. No runtimes or garbage collectors.

Frequently asked questions

If you have a question that is not listed here you may use the contact form below or write to us on Discord.

You can get help from the community by starting a discussion on Github or Discord. You may also become a sponsor and get support directly from Stalwart Labs Ltd.
Stalwart JMAP stores all metadata and settings in SQLite or in FoundationDB, a high performance distributed database. E-mail messages are stored separately from metadata, directly in the file system using Maildir or alternatively on the S3-storage of your choice.