Mind, I never used Netware.

But, originally wasn't it mostly a network system to support network printers and file systems?

BTRIEVE would run on top of that. But, as I understand it, Netware wasn't required. They just went together really well.

Finally, especially with Netware 386, they supported "NLMs". "Netware Loadable Modules". This was what let you deploy applications to the network server. Some databases ported to that I believe. I think Informix had a NLM version of Informix OnLine.

So, to me, early Netware seemed more an interesting network utility more so than what I, at least, would consider an "OS". Perhaps it was an OS, but just sealed off. At least until NLMs arrived, making the system more extensible.

I have no idea what facilities were available to NLMs, or how they were developed.

I think NLMs are effectively kernel modules. No memory protection, and only cooperative multitasking. So I doubt there were much in the way of limits on what an NLM could do.

I think they were usually developed in C. Metrowerks had a compiler that could build them, and Open Watcom can still do so as well.