&quot;And nowadays everything is in the app store, including the developer tools.  And the tools are set up so that you can only build for supported version of the OS.  It is still possible to use XCode to build an application for Snow Leopard because you can still get an old XCode install DVD and an old Snow Leopard install DVD, and if you get Snow Leopard Server you can even run it on a VM.  So no matter what Apple does, you can run Snow Leopard forever if you want to.&quot;<p>Sigh.  That makes me very happy.<p>It also makes me very happy that I saved, into cold storage, every single .iso and .pkg and ... everything ... that I ever downloaded from the apple developers site.  The old apple dev resources&#x2F;download site was too good to be true - you knew it was going to go away.