The client part no longer works, everything needs to be rebuilt for the Protobuf websocket. But you can use the WebAPI generator.
It can be installed through nimble with:
nimble install https://github.com/levshx/nim-steam
DocGen Tools:
git clone https://github.com/levshx/nim-steam.git
cd nim-steam
nimble docs
Docs on GitHub Pages: https://levshx.github.io/nim-steam/
WebAPI Generator Tools (see more in docs):
git clone https://github.com/levshx/nim-steam.git
cd nim-steam
nimble webapi