Indeed, this is very nifty. I also note that this uses
features of our SPARQL endpoint that I did not know about (the "gas
service"). It seems that this is a proprietary extension of BlazeGraph,
which comes in very handy here.
Yes, it's described here:
and it's a
service implementing basic graph algorithms such as BFS, shortest path,
PageRank, etc. I personally didn't use it too much but it may be very
useful for tasks which are naturally expressed as graph traversals.