[yjh0502]

more general, adaptive version: https://github.com/armon/libart

[fanf2]

Yes, that's pretty elaborate :-)

There's space in qp tries for jumbo nodes - they currently use flag values of 0, 1, 2, so 3 is available for byte-at-a-time branches.

[nullc]

Careful, you're going to reinvent libjudy. :P