[kingkongjaffa]

Ask questions. write everything down.

try to figure out the codebase, find the docs and the person who maintains them.

try to figure out who wrote/maintains what part so you know who to ask for help.

Figure out if you should try to get into the middle/meat of the codebase or if you should start working on the edges. (Architecture/culture dependent).

Schedule 20-30min intro/coffee call with anyone who will accept.