The Next Generation Gradebook for the Sakai CLE
For an overview of the progress so far, see https://www.youtube.com/watch?v=mO2KIkFuKdg
To get accurate notifications when other users are editing, you need to tune the editing notifications cache. Set this in sakai.properties:
memory.org.sakaiproject.gradebookng.cache.notifications=timeToLiveSeconds=10