Keep in mind finance is not quantitative finance. (edit: I just realized I didn't specify above. I'm doing quant work.) In finance (and quant work) you don't

Keep in mind finance is not quantitative finance. (edit: I just realized I didn't specify above. I'm doing quant work.) In finance (and quant work) you don't want a mistake. You want what you code to have provability, so you know what you write is what you get. This is super important. Speed in pure finance is not important. In quantitative finance the common practice today is companies roll out their own programming language that has provability like Haskell, but is closer to the speed of C++. These languages tend to be a big closer to lisp than Haskell, but it depends from company to company.