Mattermost by Stackhero is a managed instance of Mattermost, the open source team communication service, provided by the France based cloud company Stackhero. Mattermost is aimed at developers but works for any group that needs persistent channels and direct messaging, and it is normally self hosted.
Taking it as a managed service removes the operational work while keeping the open source software. Stackhero hosts on Scaleway and Hetzner, which use only renewable energy for their servers, making it a European alternative to US chat platforms for teams that want an EU supplier.
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