1. Over-focusing on technologies, rather than skills. (https://codewithoutrules.com/2018/01/18/worst-resume/)
2. Leaving out organizational context, project context. Why did you do that? Why should I care?
3. Leaving out outcomes. Don't just tell me what you did, tell me how awesome the results were!
So like "I wrote some software for the X project at company Y." Leaving out what company Y does, what the X project is, the fact that you worked alone on a really tight deadline and ended saving the company massive amounts of money.
For me, technologies actually help me contextualize how much experience the person has. When a resume says "fast learner" or "team player", well, everyone else will claim that too and it becomes somewhat of an empty claim in my mind. With that said, a bullet list of common technologies does tend to come across as a junior level of experience
> Leaving out organizational context, project context. Why did you do that? Why should I care?
This is a good point. I would phrase it as "What was the purpose of the work". IMHO, there are two types of good answers, the ones that highlight the business impact, and the ones that tie in to code quality.
> Leaving out outcomes
Overall I agree, but I think there are some types of answers that raise flags, e.g. when the acccomplishment seems like the person might be claiming credit for the whole team's effort. Heroic stories might also be a sign of team friction.
A list of technologies is just as easy to fake. So ideally it's "Because of X, in context Y, I did Z using technologies A, B, C." Rather than "I know A, B, C.".
I definitely don't take a technology laundry list at face value, especially if I see something like 2 yrs experience and a list containing Swift, React, MongoDB and [insert fad technology here]
* I see a lot of resumes for inexperienced developers that go two to three pages. I understand that this might be the norm in other countries where a CV is more common than a resume, but in the US, if you have less than five years of job experience, I expect your resume to be one page (personally, I prefer this even if you have 5-10 years experience, but I can excuse it at that point. More than ~10 years and I think that having two pages is completely acceptable and maybe even preferred).
* Typos and obvious grammatical errors are big pet peeves of mine. I don't think developers need to have outstanding spelling or grammatical skills. I do think that developers need to be detail oriented enough to catch obvious (and hopefully non-obvious) issues in their code. If you demonstrate that you didn't catch obvious issues on a very important (for your career) two page document, then how can I trust that you'll catch obvious issues in your code? As an aside, if English isn't your first language, I'll be a little bit more lax in this area, but I still expect that you'll at least have an English speaking friend look over your resume for obvious issues.
* I don't like funky formatting. It's surprising how many resumes I see with fancy formatting, presumably because the writers of those resumes want them to stick out. What sticks out to me is a well formatted and well organized, text only, black and white resume with good content.
* Take out things that are irrelevant to the job. This is especially true if your resume is over one page. For example, if you have a bachelor's degree in CS, I really don't care where you went to high school or that you were the captain of Model UN while you were there.
I would also say that these reflect poorly on the candidate:
- listing hobbies - personal website (good candidates don't need to pad their resumes with one) - links of poor quality. It's a turn-off to see a link to github full of forks of learning material from code schools, or a twitter account that is talking about overwatch.