Almost there

[Faré]

> (load (merge-pathnames "setup.lisp" *quicklisp-home*))
Minor nit: this code isn't compliant ANSI CL.
(make-pathname :name "setup" :type "lisp" :defaults *quicklisp-home*)
is the compliant version.
Indeed, if *default-pathname-defaults* has non-null HOST and DEVICE
that differ from *quicklisp-home*, you lose;
and you can't explicitly specify :HOST NIL yourself, it's not portable.

And that's the reason for UIOP:MERGE-PATHNAMES* and UIOP:SUBPATHNAME;
but you can't use them when ASDF isn't loaded yet.

—♯ƒ • François-René ÐVB Rideau •Reflection&Cybernethics• http://fare.tunes.org
The hacker: someone who figured things out and made something cool happen.
        — Alan Schmitt