[cb321]

People do game engines in Nim. ReelValley was even a commercial effort. (This is only to supplement the parent comment, not contradict.)

Your mileage may vary, but several times I've tried some single threaded thing in both Rust, C++ and Nim and the Nim came out faster (e.g. [1] had final Nim version 5.0 ms, C++ 27 ms, Rust 42 ms), not putting much effort into any, and is likely more readable to someone brand new to the language. Writing generic data structures & algos in Nim is also a true breeze/pleasure. Anyway, they are all "fast and maybe-safe by default" and all respond similarly to optimization care. There is no obvious performance disadvantage (and compiling times are much better in Nim, yielding scripting language-like code iteration).

[1] https://news.ycombinator.com/item?id=24817594