This is MARNIX, a UNIX clone.
Easy as pie but make sure that you're on a GNU/Linux system:
make clean all
HOW TO RUN
I would recommend against running MARNIX on real hardware for now. :-)
Install qemu and run it like this:
qemu-system-i386 -m 16 -no-reboot -debugcon stdio -kernel multiboot.img
Too numerous to list. It's a work in progress.