Here you are another small contribution (for the community) -but it feels like a big achievement for me (not a pro here)-.
This library wraps ipopt. This enables performing large scale non-linear optimization.
I have included a couple of examples based on hs071_c.c.
The second example uses a macro to perform a similar calculation ex02.nim which is a lot shorter and kinder to the eyes.
I hope it becomes useful for somebody.