Ok, point taken.  This discussion will be moved to an appropriate place.  However, I believe you have a sample space of 3 now.  I just checked the other Mac (also v10.4 like mine) in the office and it doesn't have ffi.h anywhere in the file system.  If you don't care as you want a mac expert to take over, I completely understand and please disregard these comments.

> (cffi-grovel:grovel-file .... #+(or gsll:macports gsll:darwinports
> gsll:fink) :cc-flags #+(or macports darwinports)"-I/opt/local/include"
> #+fink"-I/sw/include")

I'm unclear on who/what put gsll:macports onto *features*.  That's not
anything I do, nor could I.  Therefore I couldn't put it into my
source code.

The user would.  There are definitely some errors here, I didn't actually try this out.  I think it would work if the symbols were from the keyword package rather than GSLL.

I believe that it is okay Lisp style to have the user push a symbol on the features list in order to tell packages what features are present.  Like I could (push :macports *features*) before building GSLL, which, with proper reader conditionals, could allow GSLL customize the build according to a system that uses macports.  Which all becomes another way for the user to tell you where to look for paths.

Thanks for your work and thoughts on this matter,
Zach