Well atm wiki.js in beta support multiple DB formats apart from MongoDB that's currently being used in v.1.x. I have mongodb and postgres as well as mysql running, but don't wanna transfer from mongo to postgres just yet. So will wait until wiki is officially 2.0 and then I'll host it.That never occurred to me. Keep us posted.
Atm I have tried beta and its great. Safari is having problem with it, but works fine in FF (another reason I wanna wait).
Well I have just updated to latest version of Bookstacks 0.26 (via linuxserver/bookstack docker image) and I have to say that consideirng I have moved alredy a lot of data to it I just might stick with it and not migrate to wiki.js.
With multi user support, comments for pages, addition of "Shelves", versioning etc.. I see no reason atm to look for a different platform.