Been there... It&#x27;s a terrible feeling.<p>A couple of vectors to approach the situation:<p>- Start top down. Understand what the entire system or product is supposed to do at the macro level. Understand the main architectural components, what the role of each is and how they interact with each other and users or the outside world. Once you can understand the big picture, the individual lines of code have a context that helps understand their purpose and how they perform it.<p>- Discuss with your lead engineer what his expectations are for your progress. Very senior people I have talked to will claim that it takes 6 months - 1 year before a new hire can really start to contribute. Longer if it is a legacy system as you are facing. Something like, &#x27;Once I am up to speed, what kind of tasks or projects will you expect me to take on? Can you give a few specific examples (maybe things that actually are on the list today) and give a time line for how long you&#x27;d expect it to take me to get them done? This can be a bit dicey depending on the style of the manager, but it&#x27;s good to learn their style in addition to their expectations of your performance.