@gatesvp @chris__martin well, for instance, for the Debian Linux distribution, you can find the source code and binaries for all ~8000 (then) and ~72000 (now) packages all the way to March 2005. Granted, you will hit issues where architectural changes will prevent you from running binary code, but hardware emulators exists and are more and more common (because we keep creating new architectures); and yes, you can count those as 'maintenance' or dependencies.
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