Do you know very much about GPUs? Would but be viable to implement a kanren on top of cuda or something like that? Wouldn't that lend kanren insane performance gains?
and some do a lot of largely independent but very regular work that would execute quite well on a simd/vector/smt array.
people have come up with some tricks to map control flow into simd (like some really cool parser tricks), but i think in general those have regimes where they have sub-serial performance.
so maybe? if you had the magic compiler? or you provided some manual annotation support? or a robust ffi?
for sql, which has a much more limited footprint, there's been some cool vectorization work.