A media archaeologist a couple of years back stumbled upon an older Macintosh running a prototype operating system that never saw commercial release: System 7.7 was subsumed by MacOS 8 a few months later. But the early-alpha version of 7.7 still exists, and thank goodness someone with the appropriate skill set found and archived this precious and rare slice of computing history.

I love that the Special menu was renamed "Speedy" but in all other ways, this feels very much like one of the older Mac System 7 setups...with a few interesting internal testing tools and some unexpected hints about who was using the device in the artefacts left behind on the drive image.

I plan to install this on real Mac hardware soon, but it does work great right now using SheepShaver, the emulator.

http://macintoshgarden.org/apps/macos-77-pre-release

#MediaArchaeology #MediaArchaeologyLab #Mac #ClassicMac #RetroMac #RetroComputing

@spike Sorry, but this is not a "prototype operating system that never saw commercial release". It's just an alpha of MacOS 8.0, which was called 7.7 during development all the time and only changed to 8.0 very shortly before release (to somewhat distract from the Copland disaster and to stop the licensing for Mac clones). This is widely known and facts should not be bend in order to have a story. It's nothing special - there are alpha and beta releases available for pretty much all versions of MacOS.