I've just published a new version of the Quicklisp client. You can get it with (ql:update-client).
This version updates the fallback ASDF from 2.26 to 3.2.1. (This will not have any effect on any implementation except CLISP, which does not come with ASDF of any version.)
It also includes support for dists with slashes in the name, as published by Ultralisp.
Thanks to those who contributed pull requests incorporated in this update.