Hudson River Trading expectations

I’m about 1 year SDE experience in another company (ignore my current company name it was from a different job before I made transition to coding) and I had been reached out by a recruiter from HRT. I wonder what kind of things they value when considering hiring SDE. Do we need to have experience coding with super complicated algorithms/math calculations or something? C++? Or what can I do if I want to prepare for landing a job in HRT in the future? Or maybe just hedge funds in general? #tech #hudsonrivertrading