I actually went Haskell->F#->Clojure in terms of job progression, so I am ok with largely theoretical stuff.

The reason I ask is that Clojure is an easy-ish sell largely because there's a near guarantee that you will never be blocked due to lack of libraries, since you can mooch off of anything in the Java ecosystem (similar arguments can be made for F#). I hate Java, but it has been around a long time and is extremely popular, and as a result there is a library for virtually anything for it. As far as I know, there is no such guarantee for CL...unless I'm mistaken (which wouldn't surprise me).

When using it for work, did you ever get stuck because of a lack of libraries (e.g. JSON parsing, protobufs, socketing stuff, threadsafe collections)?