Deploy and Host Mattermost (Open-Source Slack Alternative) on Railway

Deploy Mattermost, the open-source Slack alternative, on Railway in one click. Mattermost Team Edition, a PostgreSQL database, and S3-compatible file storage are pre-wired — open your deployment, create the first account, and start chatting.

About Hosting Mattermost

This template deploys three services that work together out of the box:

Mattermost (mattermost/mattermost-team-edition:11.9) — the free, self-hosted Team Edition. Serves on port 8065 with a health check at /api/v4/system/ping. Its site URL (MM_SERVICESETTINGS_SITEURL) is automatically set to your Railway public domain, so redirects and notifications use the right address.
PostgreSQL 18 — Railway's SSL-enabled Postgres image with a persistent volume at /var/lib/postgresql/data. Mattermost connects over Railway private networking (MM_SQLSETTINGS_DATASOURCE), so database traffic never leaves the private network.
File storage bucket — an S3-compatible Railway bucket (mattermost-files) wired into Mattermost's file settings, so uploaded images and documents persist independently of the app container.

Why Deploy Mattermost on Railway

Slack charges per user per month and holds your team's data in someone else's cloud. Mattermost Team Edition has no per-user fees and you own the data. This template removes the setup friction — database credentials, file storage, and the public site URL are all auto-configured through Railway's reference variables, so there is nothing to wire up by hand. Scale the services vertically in the dashboard as your team grows, and your message history and attachments survive redeploys thanks to the volume and bucket.

Common Use Cases

Team communication for startups and remote teams without per-seat SaaS fees
Privacy- or compliance-sensitive organizations that must keep chat data on infrastructure they control
Developer and community chat with incoming/outgoing webhooks, slash commands, and integrations
Internal help desk and ops coordination with file sharing and persistent history

Dependencies for Mattermost

No external services required — PostgreSQL and file storage are included in this template
Railway service memory: 1 GB+ recommended for the Mattermost service for comfortable team use
Optional: SMTP credentials for email notifications and invites (add MM_EMAILSETTINGS_* variables later; without SMTP, email notifications are disabled)

Getting Started

Click Deploy Now — all service connections are pre-configured
Open the public domain Railway generates for the Mattermost service
Create the first account — it automatically becomes the system admin
Invite teammates and start chatting; add SMTP variables whenever you want email notifications

Upgrades & Customization

The Mattermost image is pinned to mattermost-team-edition:11.9; bump the tag in the service settings to upgrade. Environment, timezone (TZ), and all MM_* settings can be overridden via service variables following the Mattermost server configuration docs.