On Wed, 19 Jan 2000 08:45:06 +0100, Hrvoje Niksic said: Yes, but with a cost.. It's not a question of the package system.. The issue is the 'awkward code bloat' that Adrian mentions. At some point, you have to just say "screw it, Foobar-1.19 wirls on 21.2.19 and laoter only, you 21.1 users are stuck with Foobar-1.18", or you have to endure code that keeps accumulating more and more (if featurep()) code all over the place. For an interesting time, cd to xemacs-packages/lisp, and try this: find . -name '*.el' | xargs grep -i lucid | more And look how many places we're STILL checking for Lucid emacs (altthough to be fair, it's usually (string-match "XEmacs\\|Lucid" emacs-version) as the test). calc/calc.el even contains this: ./calc/calc.el: (error "Lucid Emacs requires RET after %s" And *how* long ago was Lucid? ;) Is the byte-compiler optimizer able to remove dead code, so at least we're not taking a performance hit on those? /Valdis