There are not so many chess implementations in LISP (at least, to my knowledge)
Here is one.
No hay muchas implementaciones del ajedrez en LISP (que yo sepa)
Ahí va una.
...On input it has array of numbers. On output it gives all variants of right solves.
It can be used for crossword verification and difficulty assesment.
I devote it to patience of my wife :).