The project always needs a messenger that can be integrated with the portal. The priority is given to open-source services – they can be “deployed” on your server and not spend money on a subscription. Today, let’s have a look at such messengers as Slack, Rocket. Chat, Mattermost, and MS Teams.
Slack is useless in the free plan due to the limitation in messages. With a staff of 10+ people, there will be practically no correspondence history due to the limitation in the number of messages. A cool messenger in terms of functionality, but not suitable for a budget project.
Rocket.Chat. Everything is fine in the free server version. The only drawback is that you need to “raise” a separate server for each command, which is inconvenient.
Mattermost. To add new commands, you don’t need to create separate servers like in Rocket.Chat. The downside is the lack of calls, both audio and video.
MS Teams. The free version is sometimes better than Slack. The main disadvantage is that you need to develop your own integration for the corporate portal.
Of course, server versions of messengers have an advantage over free cloud ones. They have access to almost all functions of paid plans in a free (Open Source) version. But do not forget that you need separate resources to support your server.
