repl hangs for ~15 seconds on each error (emacs + cider + boot) - emacs

Question

I'm facing a strange behavior whenever I invoke an error in boot-cljs-repl. The repl (actually the entire emacs) hangs for about 15 seconds and after that I see the following error message below the mode-line:
error in process filter: Lisp nesting exceedsmax-lisp-eval-depth'`
An error would e.g be calling (some-nonexisting-function) from the REPL.
Additionally I get an error message inside the REPL itself. Sorry, for posting the whole thing here - I wouldn't know right now which parts are important:
box.webgl> (some-nonexisting-function)
WARNING: Use of undeclared Var box.webgl/some-nonexisting-function at line 1 <cljs repl>
#object[TypeError TypeError: Cannot read property 'call' of undefined]
TypeError: Cannot read property 'call' of undefined
at eval (eval at <anonymous> (http://localhost:3000/main.out/weasel/repl.js:30:470), <anonymous>:1\
:124)
at eval (eval at <anonymous> (http://localhost:3000/main.out/weasel/repl.js:30:470), <anonymous>:9\
:3)
at eval (eval at <anonymous> (http://localhost:3000/main.out/weasel/repl.js:30:470), <anonymous>:1\
4:4)
at http://localhost:3000/main.out/weasel/repl.js:30:465
at http://localhost:3000/main.out/weasel/repl.js:39:4
at cljs.core.MultiFn.call.G__10839__2 (http://localhost:3000/main.out/cljs/core.js:33327:106)
at cljs.core.MultiFn.call.G__10839 [as call] (http://localhost:3000/main.out/cljs/core.js:33594:20\
)
at .<anonymous> (http://localhost:3000/main.out/weasel/repl.js:184:71)
at goog.events.EventTarget.fireListeners (http://localhost:3000/main.out/goog/events/eventtarget.j\
s:284:23)
at Function.goog.events.EventTarget.dispatchEventInternal_ (http://localhost:3000/main.out/goog/ev\
ents/eventtarget.js:381:26)

Answer 1

recently CIDER was changed to automatically supply it's own cider-nrepl and clj-refactor middleware when starting lein, so you can (should) remove these from your ~/.lein/profifiles.clj file if you have them. This will clear up this warning. (remember to update to the latest cider emacs package.
WARNING: CIDER's version (0.12.0-snapshot) does not match
cider-nrepl's version (not installed). Things will break!
This is a problem and hopefully fixing it clears up your other problems. If not, at least solving this is a prerequisite to debugging it properly.