Open-source alternative
Replace Microsoft Teams with Mattermost / Rocket.Chat
The best open-source alternative to Microsoft Teams is Mattermost or Rocket.Chat, self-hosted on Railway. Team chat and calls you host. Mattermost and Rocket.Chat replace Microsoft Teams without the Microsoft 365 seat.
Estimated save $2,100 a year.
Open the stackStart on Railway
How Microsoft Teams compares
| Microsoft Teams | Mattermost / Rocket.Chat | |
|---|---|---|
| Pricing model | Per-user subscription (Business Basic includes Teams) | Open-source or fair-code license; you pay the host |
| Hosting | Vendor cloud | Self-hosted on Railway or any VPS |
| Rough monthly cost | $7/user/mo paid yearly (Business Basic); $14/user/mo Business Standard source | Hosting only — no SaaS seat meter in this repo |
- Mattermost
Open-source team chat, playbooks, and calls
- Rocket.Chat
Open-source workspace chat already in the catalog
FAQ
- Is it free?
- The Mattermost / Rocket.Chat licenses are open source or fair-code. You still pay hosting (Railway or any VPS) and any APIs the stack calls. There is no Microsoft Teams seat or task bill on this path.
- Can I migrate from Microsoft Teams?
- Yes. Start with the workflows or data you actually use, then cut over. The Mattermost / Rocket.Chat stack page has the agent prompt and the cost table; most teams rebuild the slice that matters and leave old Microsoft Teams links until they expire.
- How do I deploy it?
- Open the Mattermost / Rocket.Chat stack, copy the agent prompt, and deploy on Railway (one service, PORT, and a volume when the app needs disk). Placeholder: Mattermost (or reuse the Rocket.Chat stack) + Postgres. Persist data on a volume. Set SiteURL. Slack's /replace/slack page stays on Rocket.Chat alone.
- What does this replace?
- Microsoft Teams. The published small-team estimate on this stack is $2,100 a year.
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