title: Nestjs - What is the right approach to have custom classes using 3rd party libraries available
body: <p>I am new to NestJS and I did not find any clear instruction to do what I need to.</p>
  <p>I wanted to build my backend using NestJS which I have never used before but only heard good things about. So the backend server I am going to build will be using a 3rd party module called ccxt from npmjs. In a normal node app, I would just create a random class for example CryptoManager, import the ccxt module and write some functions that are running on set intervals or whatever. Then I would create a controller class that instantiates an object of that CryptoManager class and from there on I can return it's responses.</p>
  <p>But how am I supposed to do this with NestJS? What do I have to do, in order to have a custom class that is running background tasks available in other nest controllers / services and so on?</p>
  <p>This class is just supposed to execute 3rd party (ccxt) module functions and store results in a database.But I want to be able to execute this classes methods from all points in the nestjs app (from all modules).</p>
  <p>I hope my question is clear, if not please let me know.</p>