RocketChat/Rocket.Chat

Rocket.Chat — a self-hosted team communication platform. Slack alternative with multi-tenant capability, regulated-industry positioning, and a long deployment footprint in regulated / government use cases.

What it is

A TypeScript + Meteor-based team chat platform supporting channels, DMs, threads, video calls, screen sharing, and federation. Self-hosted by default; commercial cloud + enterprise support available. Distinguishes itself from Mattermost / Zulip via federation + the regulated-industry / government / mission-critical positioning ("Secure CommsOS").

Key features

Channels, DMs, threads, video calls, file sharing.
Federation between Rocket.Chat instances.
Omnichannel (live chat, email, SMS, WhatsApp, social media integrations).
Apps + integration marketplace.
Self-host (Docker, Snap, Kubernetes) or commercial cloud / enterprise.
License NOASSERTION — recently moved off MIT; verify current LICENSE.

Tech stack

TypeScript primary.
Meteor framework on the backend.
MongoDB for persistence.

When to reach for it

You need self-hosted team chat with strong on-prem / regulated-industry features.
You're in a sector (gov, defense, healthcare) that mandates self-hosting.

When not to reach for it

You want zero-maintenance — Slack / Discord remove operational burden.
You're allergic to the recent licensing changes — verify current LICENSE.
Meteor as the backend stack is a known historical concern; recent versions have been migrating off it.

Maturity signal

45k stars, 14k forks, actively maintained under Rocket.Chat Technologies. The 3,737 open-issues count reflects the breadth of the platform.

Alternatives

Mattermost — comparable OSS self-hosted chat.
Zulip — threaded chat with strong public-broadcast use cases.
Element / Matrix — for federated decentralized chat.
Slack / Discord — commercial managed.

Wiki: RocketChat/Rocket.Chat