Any reason to use Mattermost now given that GitLab acquired Gitter (chat) [1]?
[1] https://venturebeat.com/2017/03/15/gitlab-acquires-software-...
I'm not sure their Gitter acquisition is intended to replace Mattermost. In fact, I wouldn't be surprised if it was integrated as an open, zero-overhead chat solution for a gitlab project, and then have it also presented in the mattermost client as a separate room for each project.
That would be a really nice integration so that as a Dev, I don't need another chat client or browser window running, but I'm also not requiring my users to install my chat client or sign in separately in order to communicate.
That said, I have no idea if their plans are similar to this or not.
[1] https://about.gitlab.com/2017/05/22/gitlab-9-2-released/#omn...
We intend to keep both around as they serve different purposes :)
JIRA was on the table too as it's more feature rich, but the costs were several times higher (especially when you start tacking on their CI tooling and stuff).
GitHub however was just too feature poor to be considered seriously - less features than GitLab and it's priced higher than JIRA.