For anyone who wants to follow the effort to revive MUSS, I have started a project on GitHub. You can find the repository here. The initial effort is focussed on creating FLIP to translate the Flocoder to compilable MUSL and I have made a start on that.
Once I have FLIP then I will need to start the process of compiling MUSL. I will probably compile the MUSL to C and then compile the original MUSL compiler (written in MUSL), but that is a little bit further off.