I don't think a god of something exists. If it does, I don't care. It might, though.
What's more important to me: life emerged from chaos, entropy will get us all, let's give this opportunity all we've got. If we don't, it's fine too - there is no game plan I am aware of so we can make our own.
Yes, after piping them through rust-bindgen, any binary can be statically of dynamically linked. I did this, it's nice that it's possible, but the PAC route others have described here is way better.
1) this is the same problem like controlling the angle of a quad copter, for which I have used PID. You can calculate the error of the position, which is in the range -180..179. Applying one PID stage to the error of the orientation yields a "desired rate of change" - it increases if the error is large or held for a long time and it's sign describes the direction of the rate of change of orientation. You can use another PID stage to give a step count power iteration (how much to turn the object).
2) integral windup is commonly prevented by just capping it. You can also use a smoother capping function which bounds the size of the integral, or lowers it on each iteration.
I am not sure this really has to do with callbacks - isn't this more due to the dangers and hassle of allowing a function with 3 arguments to be called with just one?
I am an embedded software dev and Rust would fit my job well, but I see what you are saying. However, embedded is not all for Rust and not all embedded is done by EEs. Systems programming goes from bare metal up to things like browsers and databases...