DE: Why put it on the JVM?
RH: It's designed to be useful for the work I was doing, where you have customers that have requirements that things run on one of these standard platforms—platform not meaning the OS but these infrastructures, like the JVM or .NET.
DE: And putting it on the JVM, did that get you out of doing a lot of the low-level stuff?
RH: Absolutely! I mean as a separate concern from the practicality of being able to access all the libraries, being on the JVM gives you a really nice separation of concerns between the high-level language, which is what I got to focus on, and the runtime, which is something that the JVM does an excellent job with. It's got a great garbage collector and a very sophisticated runtime compilation infrastructure. So as a language developer, you don't have to worry about emitting machine code or anything that low level. But, I'm not on the JVM just to get a free ride in terms of making it easier to implement. It was very much a part of the design of the language that you be able to touch and reach the underlying host platform, because there's a lot of value there.
DE: Libraries are part of that value, right?
RH: The amount of libraries available are really fantastic. That meant as a new language, Clojure had a ton of libraries right out of the gate. People didn't have to wait for a Clojure library for sockets or for talking to the database or for doing a GUI. They had libraries for those things right away. So they were productive with Clojure right away.
