> To be fair, the Racket team has described its fork more as a “set of patches” that other­wise stays in sync with the main branch of Chez Scheme. Still, as time passes, the two will natu­rally tend to diverge further. Whether one calls it a “fork” or “set of patches”, the result is the same: some nonzero main­te­nance cost will persist, and likely grow.

Note that now Racket run on top of almost Chez Scheme. I think there are a few patches, but almost all the changes have been upstreamed.