Chatto

Chatto is an open-source chat application for teams and communities that is meant to be free and easy to self-host. The repository contains the chat server, a command-line tool, and a bundled web front end, and the project describes itself as fully featured. It is released under the AGPL-3.0 license.

The topics describe a privacy-first design that is GDPR-compliant, and the application includes voice calls, video calls, and screen sharing in addition to text chat. The repository also hosts related components, including Runling, an independent workflow and agent orchestrator published on npm, and Authling, an identity provider that is expected to move to its own repository.

The README says cloud hosting will be available soon, so self-hosting is the supported route today, with a documentation site and releases for installation. The authors note that Chatto is built with the help of coding agents. It is a young project created in 2026 and suits teams that want an alternative to hosted workplace chat tools.