Mattermost
Secure collaboration platform. Alternative to Slack.
Open the official app on mattermost.com
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Use it free
Open the official tool or demo — no account needed.
Self-host it
Run the open-source version on your own infrastructure.
What is Mattermost?
Mattermost is an open-source collaboration platform designed for secure, mission-critical communication across teams and organizations. It enables real-time messaging, file sharing, and integration with development tools, prioritizing data control and compliance. Used by governments, enterprises, and military organizations, it addresses challenges like fragmented communication, unsecured data exposure, and inefficient workflows. By offering on-premises, private cloud, and air-gapped deployment options, Mattermost ensures operational sovereignty for sectors requiring strict data governance. Its MIT license allows customization and deployment without vendor lock-in, making it a flexible alternative to proprietary messaging platforms. The tool solves problems inherent in traditional communication tools by providing end-to-end encryption, role-based access controls, and audit logging. It caters to environments where data security and regulatory compliance are paramount, such as national security operations or critical infrastructure management. Mattermost’s ability to integrate with existing systems and automate workflows via AI-driven features reduces manual tasks, enhancing productivity while maintaining control over sensitive information. Its adaptability to both small teams and large-scale enterprises underscores its role in modernizing secure collaboration practices.
How it works
Mattermost is an open-source platform for secure, real-time collaboration, designed for teams requiring strict data control and compliance. It functions as a team chat and workspace hub, combining messaging, file sharing, and integration with development tools. The platform is tailored for mission-critical operations, such as government projects, enterprise workflows, and military communications, where data sovereignty and security are non-negotiable. Its primary purpose is to replace fragmented communication channels with a centralized, secure environment. By offering end-to-end encryption, customizable access policies, and audit trails, Mattermost ensures that organizations retain full control over their data. It is particularly suited for environments where compliance with regulations like GDPR or HIPAA is required. Mattermost supports secure collaboration through features like encrypted messaging, private channels, and role-based access controls. It integrates with tools such as GitHub, Jira, and CI/CD pipelines, enabling workflow automation. The platform’s Enterprise Advanced edition adds multi-domain management and AI-driven insights for secure, large-scale operations. Deployment options include on-premises servers, private clouds, and air-gapped environments, catering to organizations with strict security requirements.
How to use it
- 1Obtain a Mattermost server URL from your organization’s invitation email. 2. Download and install the desktop app (Windows, macOS, Linux) or mobile app (iOS, Android) from the official website. 3. Connect to the server using the provided URL and authentication credentials. 4. Navigate the interface to create channels, send messages, and integrate with external tools via the plugin marketplace. Practical tips include customizing notification settings, enabling two-factor authentication, and leveraging search filters for quick information retrieval.
What it can do
- Utility
Use cases
Assumptions and limitations
Assumptions
- source: https://github.com/mattermost
- license: MIT — free to use
- privacy: Opens an external demo
Limitations
- Requires a dedicated Mattermost server for deployment, which may necessitate IT infrastructure management.
- Limited native mobile features compared to proprietary platforms like Slack or Microsoft Teams.
- Steep learning curve for users accustomed to consumer-grade messaging tools.
- Dependence on third-party integrations for advanced automation capabilities.
- Public cloud deployment options are less mature than proprietary alternatives.
Understanding the result
Secure collaboration platform. Alternative to Slack.
Tool details
- Clearly flagged when a network request is needed.
- No account, no sign-up, and no tracking of your content.
- Powered by mattermost (MIT).
- Built with
- mattermost (https://github.com/mattermost)
- License
- MIT
- Runs locally
- No — requires a network request
- Verification
- Not yet verified
- Input
- Text
- Output
- Output
Built with https://github.com/mattermost. OpenToolVault provides the discovery and browser interface while crediting the original project maintainers.
- Built with
- mattermost
- License
- MIT
Open-source project
OpenToolVault is an independent directory. We are not affiliated with or endorsed by this project.
References
- /mattermost — GitHub Repository
Upstream project · GitHub
- MIT License
Upstream project
Frequently asked
What is Mattermost and who uses it?
Mattermost is an open-source collaboration platform used by governments, enterprises, and military organizations. It provides secure messaging, file sharing, and integration with development tools. Its focus on data sovereignty and compliance makes it ideal for sectors like national security, critical infrastructure, and regulated industries requiring strict control over information flows.
How does Mattermost ensure data security?
Mattermost employs end-to-end encryption for messages and files, along with role-based access controls to restrict data visibility. Its on-premises and private cloud deployment options allow organizations to host data internally, avoiding third-party storage. The platform also includes audit logging, ensuring all actions are tracked for compliance with regulations like GDPR or HIPAA. Enterprise Advanced features add multi-domain management and secure automation for high-stakes environments.
How do I install Mattermost on my desktop?
Download the Mattermost desktop app from the official website for your operating system (Windows, macOS, or Linux). Run the installer, then launch the app. Connect to your organization’s Mattermost server using the provided URL and authentication credentials. Once connected, you can join channels, send messages, and integrate with tools like GitHub or Jira through the plugin marketplace.
How does Mattermost compare to Slack or Microsoft Teams?
Unlike Slack and Microsoft Teams, Mattermost is open-source with a MIT license, allowing full customization and on-premises deployment. It prioritizes data sovereignty by enabling organizations to host data internally, whereas Slack and Teams rely on cloud-based infrastructure. Mattermost also offers advanced security features like air-gapped deployments and multi-domain management, making it more suitable for government and critical infrastructure use cases.
What should I do if I can’t log in to Mattermost?
Verify that you’re using the correct server URL and credentials provided by your organization. Check your internet connection and ensure the Mattermost app is up to date. If issues persist, contact your IT administrator or the support team for your organization’s Mattermost instance. For mobile users, ensure the app is configured with the correct server address and that two-factor authentication settings are properly enabled.