Metaprogramming in Nim is very powerful. But why would you use it? How is it used in the real world? We will explore the "power levels": starting from generics, continuing to templates and finally arriving at macros. We will first look at generics usage in VMath (Vector Math Library) and Jsony (JSON Parsing Library). Then we will continue on to templates and how they are used in VMath and Windy. Finally we will look macros, the top of the "power levels", and how they are used in Shady (a Nim to GLSL compiler) and Genny (Generates bindings for Nim libraries).