# Mattermost

Open-source, self-hosted team chat — Homebrew’s own listing calls it exactly that: a “Slack-alternative.”

- **Category:** [Utilities](https://notchlist.vercel.app/category/utilities/)
- **Price:** Free limited-use evaluation edition (“Mattermost Entry”) for self-hosting; Professional, Enterprise, and Enterprise Advanced plans are all “contact sales” — no public per-seat price listed on the official pricing page
- **Open source:** yes
- **Official site:** https://mattermost.com/
- **Available via:** Homebrew, Direct
- **Requirements:** macOS 12 or newer, Apple Silicon or Intel, per the Homebrew cask (separate per-architecture builds listed).
- **Maker:** Mattermost, Inc.

## Kitsmith's take

The most directly-labeled Slack alternative in this list — Homebrew’s own cask description reads “Open-source, self-hosted Slack-alternative,” independent of anything Mattermost says about itself. Channel-based messaging, threaded discussions, and 1:1 calls with screen sharing all ship in the Professional tier, with native desktop apps for Mac alongside web, Windows, iOS, and Android. The tradeoff: Mattermost has repositioned hard toward government and “mission-critical” enterprise deployments (FedRAMP, STIG-hardened images, and air-gapped installs feature prominently on its own site), and its current pricing page lists no public self-serve number — Professional, Enterprise, and Enterprise Advanced are all “contact sales,” with only a limited-use technical-evaluation edition offered for free.

## Features

- **Channel-based team messaging:** Public and private channels, 1:1 and group messaging, file sharing, and link previews across web, Mac, Windows, iOS, and Android.
- **Threaded discussions:** Follow-up conversations stay attached to their original message via a thread inbox, rather than scattering across the channel.
- **1:1 calls with screen sharing:** Built-in audio calling and screen share ship in the Professional tier without a separate video app.

## FAQ

**Is Mattermost a Slack alternative?**

Yes — Homebrew’s own package description for the Mac cask calls it exactly that: an “Open-source, self-hosted Slack-alternative.”

**How much does Mattermost cost?**

Not publicly listed at the time of this review — Professional, Enterprise, and Enterprise Advanced are all quote-based on Mattermost’s own pricing page. A free, limited-use evaluation edition is offered for self-hosted technical evaluation.

**Who makes Mattermost?**

Mattermost, Inc., led by CEO and co-founder Ian Tien, per the company’s own About page.


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Hand-verified listing on Kitsmith: https://notchlist.vercel.app/apps/mattermost/