Creator of DevOps & Node.js contractor in London. • "Clojure":, "LFE": etc, i.e. implementations of Lisp running on top of popular virtual machines. There are two advantages to this approach: # You get a lot of libraries for free, as long as the author spent a bit of time thinking about interop. # (new) Lisp code can live side-by-side with (older) Java, Erlang &c code. There is no need for a radical rewrite or any interop difficulties -- you simply write parts of your system in Lisp where it makes sense, perhaps gradually replacing older non-Lisp code. This would also mean that: "Common Lisp": is not going to get mainstream for three reasons: # It's full of what looks like cruft to beginners. # It's not straightforward to get started with. Advising newbies to learn Emacs & SLIME is not wise and doesn't work. Choosing an implementation to start with can be tricky too. # The community is not making an effort to make CL seem cool. "PLT Scheme": is not a contender either, because it's perceived as little more than a Lisp for teaching, which isn't true, but the community isn't doing much to shatter this perception. *Update* discussion over at "Hacker News":