Restore the `fullyparallel: false` override for the unsharded `Postgres with binary parameters` and `Postgres FIPS` jobs in the weekly workflow. The override was originally added to the binary parameters job in #35995 to prevent resource exhaustion on a single runner, but was dropped when both jobs moved into server-ci-weekly.yml in #36036, leaving them on the template default of `true`. Without it, the hosted runner is overwhelmed (too many server instances, WebSocket hubs, and DB connections) and the runner agent itself loses communication with GitHub mid-run, surfacing as "hosted runner lost communication with the server" at ~55-60 min into the Run Tests step. Both runs on April 27 and May 4 failed this way; the sharded FIPS variant retained for FIPS-touching PRs in server-ci.yml is unaffected because each shard handles only a fraction of the packages. Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Mattermost is an open core, self-hosted collaboration platform that offers chat, workflow automation, voice calling, screen sharing, and AI integration. This repo is the primary source for core development on the Mattermost platform; it's written in Go and React, runs as a single Linux binary, and relies on PostgreSQL. A new compiled version is released under an MIT license every month on the 16th.
Deploy Mattermost on-premises, or try it for free in the cloud.
Learn more about the following use cases with Mattermost:
Other useful resources:
- Download and Install Mattermost - Install, setup, and configure your own Mattermost instance.
- Product documentation - Learn how to run a Mattermost instance and take advantage of all the features.
- Developer documentation - Contribute code to Mattermost or build an integration via APIs, Webhooks, slash commands, Apps, and plugins.
Table of contents
- Install Mattermost
- Native mobile and desktop apps
- Get security bulletins
- Get involved
- Learn more
- License
- Get the latest news
- Contributing
Install Mattermost
- Download and Install Mattermost Self-Hosted - Deploy a Mattermost Self-hosted instance in minutes via Docker, Ubuntu, or tar.
- Get started in the cloud to try Mattermost today.
- Developer machine setup - Follow this guide if you want to write code for Mattermost.
Other install guides:
- Deploy Mattermost on Docker
- Mattermost Omnibus
- Install Mattermost from Tar
- Ubuntu 20.04 LTS
- Kubernetes
- Helm
- Debian Buster
- RHEL 8
- More server install guides
Native mobile and desktop apps
In addition to the web interface, you can also download Mattermost clients for Android, iOS, Windows PC, macOS, and Linux.
Get security bulletins
Receive notifications of critical security updates. The sophistication of online attackers is perpetually increasing. If you're deploying Mattermost it's highly recommended you subscribe to the Mattermost Security Bulletin mailing list for updates on critical security releases.
Get involved
- Contribute to Mattermost
- Find "Help Wanted" projects
- Join Developer Discussion on a Mattermost server for contributors
- Get Help With Mattermost
Learn more
- API options - webhooks, slash commands, drivers, and web service
- See who's using Mattermost
- Browse over 700 Mattermost integrations
License
See the LICENSE file for license rights and limitations.
Get the latest news
- X - Follow Mattermost on X, formerly Twitter.
- Blog - Get the latest updates from the Mattermost blog.
- Facebook - Follow Mattermost on Facebook.
- LinkedIn - Follow Mattermost on LinkedIn.
- Email - Subscribe to our newsletter (1 or 2 per month).
- Mattermost - Join the ~contributors channel on the Mattermost Community Server.
- IRC - Join the #matterbridge channel on Freenode (thanks to matterircd).
- YouTube - Subscribe to Mattermost.
Contributing
Please see CONTRIBUTING.md. Join the Mattermost Contributors server to join community discussions about contributions, development, and more.




