Framework does not include enforce events

[calvis]

This will require a bit of re-designing, since libraries like finite domain depend on a two-phase enforce; one for constraints over variables in the answer, and one for constraints over variables not in the answer. The former should be able to generate as many answers as possible, the latter should only generate one answer to ensure consistency.

[mmachenry]

Is this related to the fact that just requiring the FD library hangs? I have that issue when I run or syntax check this program

#lang cKanren
(require cKanren/unstable/fd)

I know this repo is pretty old. Is it abandoned? Is there any stable implementation of cKanren or might this repo ever be revived?