> The key innovation of the picture I lay above is that every layer in the system is now isolated and communicate with one another through d-bus services. D-bus

> The key innovation of the picture I lay above is that every layer in the system is now isolated and communicate with one another through d-bus services. D-bus is fantastic in its own right and good at abstracting functionalities. It still annoys me that Linux went down the route of hald for so long, before making the pivot to dbus (and udev). Especially since I was using FreeBSD in the 00's and early 10's, which had devd (an event-based system similar to udev, vs hald's polling system) and had to be hacked for all those years to emulate HAL's interface. It would be far less annoying if there were some benefits to HAL's approuch, but event-based systems had long since been proven in nearly every OS except Linux.