For years now Gitlab has bundled Mattermost as an integrated component for online chats, however this situation is changing, and Mattermost has announced that it is dropping support for single-sign-on (SSO). This is turn makes the integration with Gitlab unusable, thus Gitlab is now pondering dropping support altogether.
This is unfortunate timing as we are working on tighter integration between science groups and Mattermost channels.
Provisional Plan
So what are we going to do about this? For chat, we have been looking at Zulip for a while now. This a stand alone, 100% open source chat server that works just like Mattermost. It’s supports OpenID, so we can hook up to diy for SSO.
Regarding Git(lab), we like the light-weight Git hosting (called forges), like forgejo, that powers codeberg.org.
As said, nothing is set in stone, but seeing the route Gitlab is taking we will probably move to alternative sooner rather than later.
Sunsetting Gitlab/Mattermost?
It looks like Gitlab is acting prudently, but there is a chance that (our automated) Gitlab upgrade, wrecks Matttermost’s SSO authentication. If this happens logging into Mattermost stops working. C&CZ will likely have Zulip up and running before that time.
For Gitlab things won’t change much in the immediately future, longer term - and if we actually have an alternative - it will be set read-only and we will migrate off of it, to another forge, like the aforementioned Forgejo.