Besides the comment about the developer who only used left joins there was also this one: I worked with a ‘senior developer’ who, on a really big project with

Besides the comment about the developer who only used left joins there was also this one: I worked with a ‘senior developer’ who, on a really big project with lots of different coders around the country, prototyped the implementation in prolog including the JUnit tests (in prolog too). I think I actually know the answer to this one. I don't remember whether it was while I was still in school or later, but once heard someone say that they always picked a language to implement a prototype in that would never under any circumstances be used for the final system so that it was impossible to try to hack the prototype into the final system. And for the record I actually like Prolog for certain projects.