Async hooks – a concept that Node.js developers probably heard during their programming years. It is actually a module that provides an API to access asynchronous resources. In the beginning, it might sound complicated, and as a developer, you would not know what it is used for. But with getting to know this module, you will get more useful knowledge about the internals of Node.js and how they work and might find some really powerful usages for it in your server. In this talk, I will present async hooks. What are they, and how do they work? I will also show several usages I used in the server – mainly for monitoring and for performance analysing. After this talk, you will get few more useful tools to look into your server internals.