Nextcloud is an open source, self-hosted file share and communication platform. Access and sync your files, contacts, calendars and communicate and collaborate across your devices.

Gitea is a community managed fork of Gogs, lightweight code hosting solution written in Go and published under the MIT license.

Mattermost provides high trust collaboration and messaging solutions through an open source, community-powered approach. Enjoy all the productivity benefits of workplace messaging across web, mobile and PC, with unlimited archiving, search and integrations within IT-controlled private environments in public clouds, including AWS and Azure, as well as on-premise in private clouds and virtual or physical servers.