You should document your code, but not add comments! (most of the time) Here's why you shouldn't and which are the rare cases where you would write comments.
Learn the "Distributed tracing" pattern, which allows us to trace a request chain and what happens in between it.
Learn the 3 different dimensions you can scale your app, to give it high availability.
Did you know you could use Spring Data JPA in Quarkus? Find out how!
Add more flexibility to your Quarkus application by having configurable properties, allowing features/beans to be changed before runtime.