Restoring lost expertise of service

Quite often, if you do not go to startup or re-founded subdivision of the company (team or department), you have to face so-called legacy (old code or sometimes technologies).

You are lucky if this system is described at least partially. But what if it is not? What if you know nothing about it?

Anna will tell about the approaches to restoring the expertise of systems using the example of fictional system written on Java and supporting technologies.