That's not necessarily true; for things like designing proprietary languages themselves optimized for financial risk modeling, yes, you better have a CS Phd. B

That's not necessarily true; for things like designing proprietary languages themselves optimized for financial risk modeling, yes, you better have a CS Phd. But it's definitely not the case that everyone who touches functional programming on Wall Street has a Phd, and if you interview with the right group within an investment bank, the technical interviewer might very well be impressed with your Haskell experience, especially if you're going to be working closely with quants (provided he knows what it is; there's a really massive range in CS know-how within investment banks, but that's another story)