Comment by jonjacky

The nopsys/CogNOS project is more recent (commits in 2018): "CogNOS is actually a third iteration of the orginal SqueakNOS project ..."

https://github.com/nopsys/CogNOS

There is a conference paper about it, also from 2018:

https://charig.github.io/assets/papers/SCDE-DLS.pdf