You do not want real time systems design for a GUI, its a lot more work and it wastes the vast majority of processing power to guarantee performance. You just n

You do not want real time systems design for a GUI, its a lot more work and it wastes the vast majority of processing power to guarantee performance. You just need to be a careful about the amount of work you do in event handlers and split off heavy or IO work and split big updates. The problem is all concurrency is a lot harder than serial and so it tends to be something that is delayed until its really necessary so a lot of "not really good enough" handlers end up causing minor annoying delays.