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Home/Categories/Communication & Collaboration/Mattermost
icon of Mattermost

Mattermost

Open source alternative to Slack, Microsoft Teams and Google Workspace

Host team messaging with Mattermost, a self-hosted Slack alternative for channels, threads, integrations, and security-sensitive collaboration.

36.7K starsTypeScriptActive recently
Visit websiteGitHub repo
image of Mattermost
Contents
  1. 01Who Mattermost is for
  2. 02The problem it solves
  3. 03How it solves it
  4. 04Strengths and trade-offs
  5. 05Mattermost vs alternatives
  6. 06Tech stack
  7. 07FAQ
  8. 08Similar open-source tools
TL;DR

Mattermost is a self-hosted collaboration platform for secure team messaging, workflows, voice, screen sharing, and AI-enabled software delivery. It replaces Slack for regulated or security-sensitive teams that need control over chat data and deployment.TypeScript · 36.7K stars · Active recently

who it's for

Who Mattermost is for#

Security-sensitive engineering teams

Use Mattermost for incident rooms, deployment coordination, and operational chat where logs must stay on controlled infrastructure.

Skip if:

Skip if your team wants the lowest-maintenance hosted chat and has no data residency requirement.

IT teams building service desk workflows

Use channels, integrations, and automation to route internal support and infrastructure requests.

Skip if:

Skip if you need a full ticketing platform with SLA reporting as the primary system of record.

the problem

The problem it solves#

Cloud chat creates risk when incident discussions, customer data, or internal engineering decisions must stay inside controlled infrastructure. Vendor pricing and retention rules also decide how much history teams can keep and search.

how Mattermost solves it

How it solves it#

Self-hosted chat platform

Mattermost runs on your infrastructure as a Go and React application, with PostgreSQL as the backing database.

Software delivery workflows

The README calls out DevSecOps, incident resolution, and IT service desk use cases, making Mattermost more than a general chat room.

Messaging plus calls and automation

Mattermost combines channels, workflow automation, voice calling, screen sharing, and AI integration in one collaboration surface.

strengths · trade-offs

Strengths and trade-offs#

Strengths

  • Data control for regulated teamsSelf-hosting keeps messages and files under your own operational controls, which matters for defense, healthcare, finance, and critical infrastructure teams.
  • Familiar Slack-style workflowChannels, threads, integrations, and mobile apps reduce migration friction for teams moving from proprietary chat.

Trade-offs

  • -Open core packagingMattermost has a MIT-licensed core and paid enterprise features. Buyers should map required compliance, permissions, and support needs before assuming the free edition covers every requirement.
versus alternatives

Mattermost vs alternatives#

Mattermost vs Slack

Mattermost is the better choice when chat data residency, auditability, and self-hosting matter more than a fully managed SaaS experience. Slack is still easier for teams that prioritize third-party app breadth, low administration, and consumer-style onboarding.

tech stack · detected from GitHub

What it's built on#

Languages
GoJavaScriptTypeScript
Frameworks
ExpressReact
Databases
PostgreSQL
Infrastructure
AWS
Tooling
Webpack
frequently asked

FAQ#

Is Mattermost self-hosted?

Yes. Mattermost is built for self-hosted deployment and also offers managed options.

What does Mattermost replace?

Mattermost commonly replaces Slack or Microsoft Teams for teams that need stronger deployment control.

What database does Mattermost use?

The README says Mattermost relies on PostgreSQL.

also worth a look

Similar open-source tools#

Rocket.Chat

Rocket.Chat

Self-hosted team chat with voice, video, and omnichannel support

45.3KTypeScriptMIT
Prose

Prose

Decentralized open source workplace with chat and docs

56VueMPL-2.0
Adapt

Adapt

Lightweight self-hosted messaging platform for teams

13TypeScriptAGPL-3.0
SpacebarChat

SpacebarChat

Free open source Discord reimplementation with full API parity

2.2KTypeScriptAGPL-3.0
Converse.js

Converse.js

Self-hosted web-based XMPP chat client for any server

3.3KJavaScriptMPL-2.0
Revolt

Revolt

Self-hosted open source Discord alternative with servers

3.1KRustAGPL-3.0

Repository

Stars
36.7K
Forks
8.6K
Latest
v11.6.2
Last commit
67 days ago
Last verified
May 13, 2026
Repo
mattermost/mattermost ↗

Additional details

Language
TypeScript
Open issues
865
Contributors
1,203
First release
2015

Categories

Communication & CollaborationSecurity & MonitoringIT Management

Tags

ChatSelf HostedWorkflow AutomationSecurityDeveloper ToolsChatbots