This will eventually be some kind of wiki slash CMS because why not.

Design goals

WYSIWYG editing: ideally you should be able to click edit and the only difference is that now you have a cursor and toolbar.
No mandatory JS for read-only access.
Single-sign-on: get authentication including group membership from an external service rather than make everyone remember yet another username and password and admins keep yet another role table up to date.
Be able to hold at least some binary files (images, mainly).

Non-goals

Some of these might creep back in in the future.

Be a conventional static site generator that works from an easy-to-edit directory tree with YAML front matter and the like. Previous attempts at this project failed partly because of the complexity of the on-disk layout involved.
Have fancy stuff with templates and scripts like Mediawiki does. This was the other main reason previous attempts failed. While undoubtedly useful, they really need a lot of special handling.
Support really big files (more than a few megabytes). Those should be put either on a generic host with good support for huge files, or one specialised for the handling a particular kind of content needs (re-encoding/muxing video for DASH compatibility, generating tile pyramids for huge images, etc).

See also notes/ for stream of consciousness rambling.