03.15.08
What I’ve Learned From Programming In Lisp
Two years ago I landed a job at ITA Software, which Paul Graham called one of the “ten or twenty places where hackers most want to work,” along with Google. And one of the interesting things about ITA is that the majority of their software is written in Lisp.
Now before starting there, my experience with Lisp was about the same as most CS grads. I’d used it as an undergrad in a programming languages course, as well as an AI course on natural language processing. And my thoughts about it were pretty standard: it’s a functional language, so if you’re going to use it you’re best off doing recursion and avoiding assignment statements; and dynamic typing and garbage collection make it slow.
Boy, was I wrong. It turns out, Lisp is a lot more practical than that, and we use it for the search engine that powers Orbitz.com, Kayak.com, and most of the U.S. airline websites, among others. The main things I’ve learned are: