* Use an IDE (Like IntelliJ Idea) * If there's no architecture-document that gives a short (3-5) page overview on the layout of the code then start writing one

* Use an IDE (Like IntelliJ Idea) * If there's no architecture-document that gives a short (3-5) page overview on the layout of the code then start writing one. * Skim through the folders / packages / classes and write down a few obvious questions that pop into your mind while "speedreading" the code. * Try to make an improvement to see how the whole CI/CD process works. * Look through the list of direct dependencies / libraries and see where they are used.