Comment by smeg_it

I had to look and skim to re-familiarize myself with SeL4. It's and older project that really never made it, from just a quick glance. It seems to basis or at least inspirational to more modern kernels. From the wiki, that seems to include Redox. I couldn't find much about sculpt, but it was submitted to distrowatch in 2018 and is still under the "not ready" section of their waiting list. I don't think there is really any usable FOSS OS using a microkernel. Last I remember reading, the ones most in use are highly specialized commercial projects. As far as I know Redox was the closest but it really hasn't been really actively developed (again, correct me if wrong). It hasn't been abandoned i.e. there seems to be development, but it's a long way from an end user OS at this point, from what I remember reading and no big strides have been made (again, maybe wrong)