They depricate some methods (very rarely and reasonably) and add new enums or struct versions to existing ones, but never change existing semantics, leave alone method signatures. As I said elsewhere, I invite you to find examples of actually destructive Native API changes.
The interface also allow to comment, post and interact with the original HN platform. Credentials are stored locally and are never sent to any server, you can check the source code here: https://github.com/GabrielePicco/hacker-news-rich.