So I have this teammate who is much older than I which is probably the reason why he earns more than I. He has tons of experience on other aspects of software engineering but when it comes to iOS development (which is our job), it is clear that he is underperforming. Now I just had a significant salary raise but still significantly lower than what he makes. I can't directly bring this up to my supervisor because of the NDA regarding salaries, but it's clearly causing my demotivation and hurting my overall job satisfaction.
I'd really like to stay, it's a great company to advance my skill,s but salary-wise, I also needed to feel that I'm compensated fairly. I guess what I'm asking is, how do I really manage the stress that I feel about this setup?