I worked with Andy on Crash 1 and 2. GOOL (predecessor to GOAL) was rough around the edges then, but incredibly productive to work in once you got the hang of i

I worked with Andy on Crash 1 and 2. GOOL (predecessor to GOAL) was rough around the edges then, but incredibly productive to work in once you got the hang of it -- for all the reasons lisp hackers routinely cite. Then, at ITA, we used Lisp for the QPX airfare pricing system. Both projects used lisp because the early people at both companies came out of the MIT AI Lab: Andy and I at Naughty Dog; Jeremy, Carl, and I at ITA. The issue with lisp -- especially in light of decent alternatives like Ruby and Python -- is that it's hard to find developers. Yes, you can hire from the higher-than-average-talent set of current lispers. But that's a finite and shrinking set. I think that both Andy and Carl (who wrote the basis of ITA's lisp airfare system) would probably tell the current crop of startup hackers to use a more popular dynamic language. Personally, I'm using Python now, and Peter Norvig's comment about the psuedocode-like nature of Python really resonates with me. But the main reason the popular dynamic languages are winning now, IMO, is all the code you don't have to write. Look at CPAN, PyPi, and whatever the Ruby equivalent is: there are hundreds of really well-written open source modules to do all the things you need to do on a big project. CPAN was first, but Perl poses so many syntactic challenges that it's hard to use it for a big project. In terms of productivity, no language design can compete with not have to write code at all. That's the bottom line for me these days.