congrats on shipping michel - it's very cool that you've wrapped this into a PG extension. The breadth-first search looks interesting. Do you have some more docs or a simple example with table data?
One request for the "todos" at the end would be a small docker container with onesparse pre-installed - it would help a lot for getting started
Also I may have missed this, but are there more docs yet, or just the readme for now?