Mattermost
The Mattermost channels allow communication within and accross working groups.
Plateforms are tools to support team members in their work - access is limited.
Resources are organised in such a way that anyone will be able to contribute - work in progress.
The MediaWiki, powered with semantic forms, has two purposes. First it is a way to manage resources. Second, it is the extension to manage the multilingual aspect of the scientific journal Education Ouverte et Libre - Open Education.
Etherpad supports working groups in their collaborative writing and allows information across groups for synergies.