And the database can be setup to sync with a self-hosted CouchDB instance.

While that works, the original appeal of Tiddlywiki was that you could open a file in your browser, type away, and save naturally. Once you get into "self-hosted", you just have a regular old wiki. I used it everyday for several years but gave up once the transition happened. I keep trying to go back, but it just can't compete with files edited in a text editor and stored locally.