I am joining a new company as senior software developer. The team consists of another 4 developers, 1 of whom is a senior developer, say his name is X. The senior developer will be my mentor and coach. He will supervise my onboarding program, and most likely give feedback on my probation period. I just learned that this guy, is very interested in becoming a team lead, which is the same position I joined this company for: the job title was "Senior developer with potential to become team lead".
X, to me is a very competent. However, I am in situation, where I have to compete with the person who is going to show me stuff, and teach me things. Although in total I have more experience than him. In this company's environment, he is far ahead of me. He has been there for almost 4 years. Technically, he is much more familiar with tech stack that is being used. In fact, he witnessed how this stack has been developed. I personally think he is in a very advantageous position over me. However, I am determined to not give up, (without screwing up things).
My question, what are the Dos and Don'ts that would help me to succeed in such an odd competition, given I am just starting.