--- title: Slack Who? This Self-Hosted Chat App Just Went Open Source description: Chatto is a new self-hosted team chat application that has just gone open source under AGPL-3.0+. Built by a solo developer, it offers channels, rooms, file... canonical: https://daily.dev/posts/slack-who-this-self-hosted-chat-app-just-went-open-source-1ph9xjapk twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Slack Who? This Self-Hosted Chat App Just Went Open Source | daily.dev og:description: Chatto is a new self-hosted team chat application that has just gone open source under AGPL-3.0+. Built by a solo developer, it offers channels, rooms, file... og:url: https://daily.dev/posts/slack-who-this-self-hosted-chat-app-just-went-open-source-1ph9xjapk og:image: https://api.daily.dev/og/posts/1PH9XJApk.png og:image:alt: Slack Who? This Self-Hosted Chat App Just Went Open Source og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # Slack Who? This Self-Hosted Chat App Just Went Open Source **[It's Foss](https://daily.dev/sources/itsfoss)** · 3 min read · 9 upvotes · 0 comments ## Summary Chatto is a new self-hosted team chat application that has just gone open source under AGPL-3.0+. Built by a solo developer, it offers channels, rooms, file sharing, roles and permissions, screen sharing, and end-to-end encrypted voice/video calls. It currently lacks dedicated desktop or mobile clients, but the roadmap includes a Slack migration tool, GDPR-compliant data export, bot accounts, and more. A hosted cloud option on European infrastructure is also entering public beta soon. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### What license is the Chatto self-hosted chat app released under? Chatto is released under AGPL-3.0+, with some components carrying Apache-2.0 license exceptions. It was built by developer Hendrik Mans as a self-hosted alternative to Slack, Microsoft Teams, and Discord, and is still pre-1.0, lacking a stable release and dedicated desktop or mobile clients. _Track new self-hosted Slack alternatives like Chatto as they mature on daily.dev._ ### Does Chatto have a mobile or desktop app? No, Chatto currently has no dedicated desktop or mobile client. Both are listed on its roadmap but remain in the discovery phase, meaning the team is still deciding whether to build them at all, alongside plans for a Slack migration tool, GDPR-compliant data export, and thread management features. _Compare self-hosted chat tools by client support and roadmap maturity on daily.dev._ ### Is there a hosted version of Chatto for teams that don't want to self-host? Yes, Chatto Cloud is entering public beta and will run on European-owned infrastructure, offering automatic scaling and nightly backups. Data portability is promised to avoid vendor lock-in, letting teams move data in or out of the hosted service if they later choose to self-host instead. _Weigh self-hosted versus managed chat options like Chatto Cloud on daily.dev._ ## Similar posts on daily.dev - [Dock — Team chat that doesn't suck](https://daily.dev/posts/dock-team-chat-that-doesn-t-suck-t2pjqjjhl) · Hacker News · 0 upvotes · 0 comments - [How we picked LibreChat — and ended up with a Slack agent](https://daily.dev/posts/how-we-picked-librechat-and-ended-up-with-a-slack-agent-w8rsmk8or) · Metabase · 0 upvotes · 0 comments - [Ando wants to take on Slack with a team messaging app that lets humans and agents work together](https://daily.dev/posts/ando-wants-to-take-on-slack-with-a-team-messaging-app-that-lets-humans-and-agents-work-together-kioasvlok) · TechCrunch · 0 upvotes · 0 comments --- Tags: [#open-source](https://daily.dev/tags/open-source), [#slack](https://daily.dev/tags/slack) [View this post on daily.dev](https://daily.dev/posts/slack-who-this-self-hosted-chat-app-just-went-open-source-1ph9xjapk) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"Slack Who? 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