You’re very welcome to contribute to shardbox. It’s been kind of sitting around for some time, waiting for new features ;) If you’re interested, I’m happy to guide you in.
Another similar/related project that just exists as an idea yet is Hosted documentation site
Contributing to either of the existing or planned projects is probably more useful to the community than launching a completely new one with a similar scope to what already exists.
I think the most relevant sites should be listed on the communit page.