I'm running cl-json 0.3.1 and I seem to encounter the following issue on OpenMCL: (encode-json-to-string '(("x" . "blah"))) => "[[\"x\",\"l\",\"a\",\"h\"]]" On SBCL this works as expected: (encode-json-to-string '(("x" . "blah"))) => "{\"x\":\"blah\"}" I could use 'encode-json-alist-to-string', but I'll run into the same problem with inner alist elements of the list (I have an alist of alists). -- Regards, Slava Akhmechet.