I work with Devtools team 

who uses ci.centos.org as the build machine

and we use Mattermost for collaboration 

recently, we did a poc on Jenkins-mattermost plugin

which posts build information into mattermost channels 

so if you guys can install Jenkins-mattermost plugin on ci.centos.org

we can start implementing it for our projects on ci.centos.org

thanks & regards,

sgk