[cauterized]

This. 1000 times this.

It's ok to go to a hackathon to meet people in general and to maintain the hope that you'll make a connection with someone you find attractive.

It's not ok to try to flirt at a hackathon with someone who is doing her darnedest to be taken seriously as a professional. You have no idea how frustrating it is to have people take more and earlier note of the fact that one has two X chromosomes than of one's intellectual abilities, especially in a nominally professional setting. And that's before we even get to dealing with actual unwanted advances.