Now that we know how to improve our code efficiency, we can learn how to make it work on multiple platforms and how to make sure we take advantage of all possible native optimizations, while we make the code faster and easier to implement. Metaprogramming allows us to do all that with really easy code snippets, and you probably know some of these features.

In this chapter, you will learn how to use the following macros and configuration items built in with the compiler and the standard library:

• Attributes
• Crate features
• Macros
• Nightly functionality