I think most of us strive to make our code run smoothly, read logically, and altogether function well. But for those who really enjoy taking the time to figure out how to optimize already good code (whether it's their own or someone else's), where do these individuals best find themselves in the programming world?
Whether that optimization is to improve on the current algorithm implemented in their project, take the time to make minor differences in performance, studying the run time of loops and conditionals in specific a language (for example, 3 or less
if else statements are generally much quicker than 3 or less
switch statements is some languages), or clean up code (useless variables, better modularize existing functions, etc.).
I imagine that a lot of these folks find themselves at home on projects critical to hardware performance, like fields related to microarchitecture. Anything else?