[mossity]

The points about the JVM not being able to guarantee that your code won't block the thread apply; it's left up to you to do it. This doesn't come as any surprise to me, nor I would guess to most users of the library, so I'm not sure this is really that damning. Core.async doesn't use bytecode weaving or fork/join, so those criticisms don't specifically apply.

[MCRed]

It's damning because, rather than outsource the issue like the library makes you think you are doing (or like anyone writing erlang code actually is doing) you still have to deal with the hassle and the risk, so you're not really buying much.

[village-idiot]

Except you're using it Clojure, which makes it easier to avoid that kind of stuff and easier to spot when you count on Java APIs directly.