I played around with this a year or so ago. Very interesting how a mouse interface can be built with the bare minimum of functionality, just enough to be able

I played around with this a year or so ago. Very interesting how a mouse interface can be built with the bare minimum of functionality, just enough to be able to run a program by middle-clicking some text. I struggled to get a hello world to compile though, the error message was too terse to be helpful. I think Modula-2 provided more of a realistic system to base real software on, whereas Oberon has been stripped to the bone to enable the whole CPU and OS to be implemented by one person. They've gone too far along the minimalism spectrum to be very useful. However it provides inspiration that an OS and user interface can be implemented from scratch.