My personal highlight: "It had a novel event-handling system capable of supporting arbitrary user-defined events. The event system identified events by pattern

My personal highlight: "It had a novel event-handling system capable of supporting arbitrary user-defined events. The event system identified events by pattern-matching. Q: What kind of high-level events would that be? Could the user define those? Mikel: Yes. The idea was that you could plug a sequence of lower-level events together and use a property sheet to perhaps parameterize them, thus creating a novel kind of event. Sort of like constructing AppleScripts by recording UI actions, but in smaller, easier to understand and easier to debug pieces. (One of the things I wrote for the automated testing system was an application that watched what the user did and constructed a representation of the observed actions that could be replayed on another system; it represented actions not in terms of low-level MacOS events, but in terms of abstract state transitions described in terms of frames that represented application features, so that moving to a different machine with different screen layout and so forth would not break the playback. Some of the ideas for the event system came from combining that experience with the experience of Jim Grandy, who actually wrote the event system, and who had earlier worked on Garnet.)" The future of OSes, folks!... and of applications too I'd say. It's surprising how "advanced" techniques can be very helpful even in "simple and common" cases, I've been thinking lately.