YesWiki is a free software developed under the GPL licence.
It has been developed for creating and managing websites, in a collaborative way.
This tool is promoted by the French Ecovillage Network (https://www.colibris-lemouvement.org ) so that the ecovillage inhabitants can remotely collaborate on their project. For instance, one way to enable a easy collaboration between the website users is that everybody can access to the "edit a page" function only by double-clicking on the page: this function has been authorized on this page, you can try!
For more information, you can visit: https://www.yeswiki.net