OJOS (the Original J Operating System), _(aka) Platypus is an *(OS) which <cite>.. aims to be a small experimental, extensible _(kernel) that provides a hardware abstraction layer and loadable module support. It is designed to allow new ideas in operating system theory to be tested easily. The Platypus version will include the _(microkernel), pieces of the hardware abstraction layer, multitasking, and memory management. [..]</cite>

Quite interesting is the idea of a _(Forth)/_(Lisp) mix for system programming (see the J-Language on the site below; see also _(RPL) and _(POP-11)).

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  <li>_("OJOS:Platypus 6" | http://ojos.sf.net/), an original operating system by Nathan Whitehead.</li>
</ul>
