Slack is the solution most teams think of first when they are in the market for a chat application. It is known for being feature-packed, fast, and consistently updated, making it a go-to for millions of teams across the world.But no matter how good it is, it is not open source. 🙃Thankfully, the open source space has no shortage of alternatives. Rocket.Chat, Mattermost, Zulip, and Matrix-based clients like Element have all built up loyal followings among teams who want to own their data.Now there's a new name to add to that list. It's called Chatto, and it's still early in its development cycle, with a stable 1.0 release yet to arrive.Chatto goes openAfter spending the past few months developing Chatto, Hendrik Mans has decided to offer the project openly under AGPL-3.0+ with a few Apache-2.0 exceptions for certain components.It's built as a self-hosted option for teams who would otherwise reach for Slack, Teams, or Discord. Hendrik wanted something light on resources, simple enough that an administrator can just run the executable and get started.It covers the essentials you would expect from a chat app. That includes channels, rooms, file sharing, video embeds, and a roles and permissions system for fine control over which user gets what kind of access.You also get screen sharing, along with end-to-end encryption on every voice and video call, and the number of people that can join comes down to what kind of capacity your server has.Going forwardRight now, there's no dedicated desktop or mobile client. Chatto's roadmap lists both as something that could be worked on, but they're still in the discovery phase, meaning that they are still deliberating on whether to offer those.Beyond the client apps, the roadmap lists a dedicated Slack to Chatto migration tool, along with GDPR-compliant data export, thread locking, and thread deletion as planned feature additions.Hendrik is currently working on new room types, bot accounts with dedicated API tokens, Chatto hub integration, and server-wide user suspension. Next in line are an emergency lockdown mode for admins, slow mode, in-app message reporting, and server invites.For anyone who'd rather skip the self-hosting altogether, Chatto Cloud is entering public beta soon too. It'll run on European-owned infrastructure, with neat perks like automatic scaling and nightly backups.Don't worry about vendor lock-in either, as moving data in or out of it will be made accessible.Suggested Read 📖: Best Open Source Slack Alternatives