Baïkal

Baïkal is a small, self-hostable groupware backend that provides CalDAV and CardDAV services for syncing calendars, tasks, and contacts across devices and desktop/mobile clients. It is built on top of the SabreDAV stack and is designed to be easy to deploy and administer.

Key Features

• CalDAV server for calendars and tasks (VTODO) compatible with common DAV clients
• CardDAV server for contact sync using vCard
• Web-based administration panel to create/manage users, address books, and calendars
• Multi-user support with per-user collections (calendars/address books)
• Uses an SQL database backend (SQLite by default; also supports MySQL and PostgreSQL)
• Standards-based DAV interoperability via the SabreDAV library

Use Cases

• Sync personal calendars/tasks between macOS/iOS, Android (DAVx⁵), and desktop clients
• Provide shared calendars/contacts for a family or small team without a full groupware suite
• Run a lightweight DAV endpoint behind an existing web server/reverse proxy

Limitations and Considerations

• Focused specifically on CalDAV/CardDAV; it is not a full mail/chat/collaboration suite
• Interoperability depends on client DAV support; some clients may require extra configuration

Baïkal is a good fit when you want standards-based calendar/contact synchronization with minimal overhead. Its simple admin UI and SabreDAV foundation make it practical for small deployments that need reliable DAV services without additional groupware components.