The typeface is Computer Modern, which is an absolute giveaway for TeX.
Personally, i find the use of LaTeX a small red flag. Using it certainly does send "a subtle but clear message", but it's not that you love software engineering, it's that you're willing to waste time fiddling around with abstruse technical stuff rather than doing something useful.
That is such an awful take. There are so many professional-looking LaTeX templates online, associating it with "willingness to waste time" and actually ditching a candidate shows that you likely don't know how to recruit anyway.
For me I would have to buy/pirate and install Windows and buy/pirate Office. Or make a Google account and learn to use Google documents for the first time. Both of those are companies I think are unethical and will violate my privacy. Libre Office doesn't make documents that look nice to me. I used LaTeX for hundreds of hours at university so it is really not hard to me. The laziest option to me is definitely LaTeX, and I am a lazy person that doesnt like to waste time fiddling around with abstruse technical stuff
It's the least painful way to create a high quality PDF. And "fiddling around with abstruse technical stuff" (not that I agree with the characterisation) is something probably 80% of HN enjoy.
Personally, i find the use of LaTeX a small red flag. Using it certainly does send "a subtle but clear message", but it's not that you love software engineering, it's that you're willing to waste time fiddling around with abstruse technical stuff rather than doing something useful.