The group and team chat application Chatto is now open source, allowing users to self-host the software for free. Developed over the past year, Chatto aims to provide a compact, snappy, and privacy-focused alternative to existing chat platforms. Its self-hosting setup is designed for simplicity, requiring just an executable to run and serving its own frontend.

Chatto prioritizes data protection with end-to-end encryption for chat and voice/video calls, storing data encrypted at rest with per-user keys. Each server supports a single community without data federation or third-party tracking. The client can connect to multiple servers simultaneously, and users can host separate communities by running multiple Chatto processes. Binaries are available for Linux, macOS, and Windows.

Alongside the open-source release, Chatto Cloud will soon enter public beta, offering paid hosting for Chatto servers. This service will feature automatic scaling, nightly backups, and zero-downtime upgrades, with European infrastructure planned for launch and more regions by early 2027. Chatto is currently at version 0.4, considered stable for production, with version 0.5 focusing on content reporting and moderation features. The project anticipates reaching version 1.0.0 within 6-12 months.