I haven't dabbled in game programming since the 90s, but a quick look at [the
list of available engines](https://en.wikipedia.org/wiki/List_of_game_engines)
shows many choices. I hope the Nim game dev ecosystem picks a good
[Copyfree-licensed](http://forum.nim-lang.org///copyfree.org/standard/licenses)
C/C++ library [(not zlib,
etc)](http://forum.nim-lang.org///copyfree.org/standard/rejected) to focus on
and makes good bindings.
[Godot](https://en.wikipedia.org/wiki/Godot_\(game_engine\)) seems to be a very
strong contender.