While the technology is impressive, the author seems to have lost interest, and moved on to working on something called Consus [2], which has also been abandoned (no activity 2018).
Hyperdex never became popular, and a problem all along was that the author — a very talented developer, from what I can tell — seemed more invested in his projects from the perspective of academic research (he developed Hyperdex at Cornell, I believe) than in delivering a practical, living open source project. He tried to form a company around Hyperdex (the transactional Warp add-on was commercial) even though nobody seemed to be using it; and he was the sole developer. I actually submitted a PR at one point to fix a build problem, but the author was completely unresponsive; you can't really do open source that way.
I think the Warp code was actually open sourced when the author realized they had failed to commercialize it, but I'm not sure; it's been a long time.