Here's the question that should be featured on HN: http://quant.stackexchange.com/q/306/35 http://quant.stackexchange.com/q/306/35 Essentially, C++ is popular

Here's the question that should be featured on HN: http://quant.stackexchange.com/q/306/35 http://quant.stackexchange.com/q/306/35 Essentially, C++ is popular because of existing code, particularly proprietary third-party libraries. And you are correct; even HFT shops will use languages other than C++, which is why anyone who's actually worked in this industry will know that the answer to the question of popularity is not performance. And that's why I hate that SE question so much. It was asked by someone outside the industry and is mostly answered by people outside the industry.