An ambitious MUD engine I wrote in C many years ago, while in a manic state and over the course of a few months.
A lot of it was me reinventing the wheel just to prove to myself I could.
Using 3rd party libraries or larger languages would have saved me probably around 90% of the time I spent. I tested it for bugs meticulously, but wouldn't advise using it today.
mud has the following dependencies: zlib pthreads epoll check (the unit testing framework) gcc/g++ angelscript (2.34 included)