This ‘looks’ cool but I had to read a lot and still had to make some guesses about what it does.
How about a comparison of some real world use cases? For example, could I use this to store and query some structural information that might come from an hOcr or ALTO formatted ocr output? Can OCR even be plugged in? Can I intelligently index the diff of multiple versions of a file and query that?
I have no clear idea ‘cos the team behind it are so focussed in their literature on the technical detail.