This. Also, quiz yourself about the system, maybe allocate 15mins just for that a day. Why do we need X? How are these parts connected? Are there connections th

This. Also, quiz yourself about the system, maybe allocate 15mins just for that a day. Why do we need X? How are these parts connected? Are there connections that are different? Why? Additionally, try to deeply understand the business logic. As a former dev who currently works on product, I'm often surprised how long it takes for developers to come up with solutions, which I can generate on the spot. I tend to believe there's no difference in technical skill, I just have a lot more context knowledge about what the system is supposed to do, making me more confident and thus faster in making technical decisions, despite having spent only a comparatively tiny fraction of time in the code base.