It seems to me you should find a different team, or a different job. Stop worrying about who gets the credit. Try to get the project done as best you can.

"kept on telling everyone he was working on the project in stand ups, or at best how I’m helping him" - what do you say at the project stand ups?

@JosephDoggie I agree about doing my best, which I am, but knowing that someone else is actively stealing credit for my work is just upsetting. I wouldn’t shout about my work being mine normally, but someone actively trying to convince people that’s my work is theirs just kills motivation.

@LaconicDroid typically I’ll say I’m working on my project and then that I’m working on the project I got from him. He just spins that as though he’s got me helping out or something. Recently when I’ve said things like “the project I’ve inherited from [name]” he’ll tell people how he’s helping me out (and not in an equal way - he frames it as mentoring me).

It is amazing what you can accomplish if you do not care who gets the credit. Harry S Truman

Of course, I could take credit for Harry S Truman's quote, it seems legitimate!

Does this answer your question? Coworker who likes to take credit for work that is not theirs

@gnat I think the power differential of them being more experienced and having worked here longer does complicate matters a bit compared to that question, although it’s helpful all the same :)

@joeqwerty that’s very reductive. I take pride in my work and I want it to reflect on me, not someone who has nothing to do with it. To suggest that means I’m not “a team player” is ridiculous. What I’m not willing to do is work on my projects and his (which I am doing because I am a putting the team’s interests first) only for him to intentionally take all the credit. That’s called being taken advantage of.

Can you rewrite the question? The title sounds like you're a junior and a senior is giving you a hard time. The first half sounds like you're the senior, and some less-seniors resist you because of Dunning-Kruger syndrome. The end sounds like you're asking how to be assertive and not let people steal credit. It will be hard to give a good answer with so many different things in one question, because usually posts here are short.

@amnesiacRAM - Let me boil it down and paraphrase it for you: "I'm great. They're horrible. He's inept and couldn't program his way out of a wet paper bag." - Maybe get rid of all of that nonsense in your question and it would come off as being more reasonable.

Are you a junior or just new at this company? Are you the senior’s peer or leader on this project? All of these are important details.

@PeterMortensen added :)

Does everyone agree that you were hired "to help improve coding standards and development practices"? Or have you noticed the need and taken it upon yourself? Management may feel that way, but your peers may not.

It doesnt sound like a good place to work. I would get out of there ASAP.

"How can I make it clear to everyone that this is my work (and just mine)?" git blame and/or git log. This is software dev, I don't understand how this is even a thing.

It still would help to know if you’re new to the workforce in general or just to this job? It wildly changes the calculus of the situation. If you’re 5 months into your first job you could have unknowingly misread the situation and the senior could in fact be mentoring you (perhaps passively with the boss’ quiet direction). If you’re a veteran who’s just new to this job that’s probably not the case and your assessment of the situation is most likely spot on. So the accuracy of our advice to you hinges on having some idea of how junior you are to the workforce.