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 =={{header|Emacs Lisp}}==
-A JSON encoder and decoder is in package json, so load it first:
-<lang Lisp>(require 'json)</lang>
-===Decoding===
-<lang Lisp>(setq example "{\"foo\": \"bar\", \"baz\": [1, 2, 3]}")
-(json-read-from-string example)
-</lang>
-{{out}}
-<lang Lisp>((foo . "bar")
- (baz .
-  [1 2 3]))</lang>
-===Decoding, representing data as property lists===
-<lang Lisp>(let ((json-object-type 'plist))
-   (json-read-from-string))</lang>
-{{out}}
-<lang Lisp>(:foo "bar" :baz
-      [1 2 3])</lang>
-===Decoding, representing data as hash table===
-<lang Lisp>(let ((json-object-type 'hash-table))
-  (json-read-from-string example))</lang>
-{{out}}
-<pre>#<hash-table equal 2/65 0x1563c39805fb></pre>
+{{libheader|Jansson}}
-===Encoding===
-<Lang Lisp>(json-encode example-object)</Lang>
+Emacs 27.1 offers native JSON processing using the Jansson library.
+<lang Lisp>(require 'cl-lib)
+(cl-assert (fboundp 'json-parse-string))
+(cl-assert (fboundp 'json-serialize))
+(defvar example "{\"foo\": \"bar\", \"baz\": [1, 2, 3]}")
+(defvar example-object '((foo . "bar") (baz . [1 2 3])))
+;; decoding
+(json-parse-string example) ;=> #s(hash-table [...]))
+;; using json.el-style options
+(json-parse-string example :object-type 'alist :null-object nil :false-object :json-false)
+;;=> ((foo . "bar") (baz . [1 2 3]))
+;; using plists for objects
+(json-parse-string example :object-type 'plist) ;=> (:foo "bar" :baz [1 2 3])
+;; encoding
+(json-serialize example-object) ;=> "{\"foo\":\"bar\",\"baz\":[1,2,3]}"</lang>
+{{libheader|json.el}}
+<lang Lisp>(require 'json)
+(defvar example "{\"foo\": \"bar\", \"baz\": [1, 2, 3]}")
+(defvar example-object '((foo . "bar") (baz . [1 2 3])))
+;; decoding
+(json-read-from-string example) ;=> ((foo . "bar") (baz . [1 2 3]))
+;; using plists for objects
+(let ((json-object-type 'plist))
+  (json-read-from-string)) ;=> (:foo "bar" :baz [1 2 3])
+;; using hash tables for objects
+(let ((json-object-type 'hash-table))
+  (json-read-from-string example)) ;=> #<hash-table equal 2/65 0x1563c39805fb>
+;; encoding
+(json-encode example-object) ;=> "{\"foo\":\"bar\",\"baz\":[1,2,3]}"
+;; pretty-printing
+(let ((json-encoding-pretty-print t))
+  (message "%s" (json-encode example-object)))</lang>
 {{out}}
-<pre>"{\"list\":{\"cons\":[[\"quote\",\"x\"],2],\"cons\":[[\"quote\",\"y\"],\"a string\"]}}"</pre>
+ {
-===Encoding, pretty printing output===
+   "foo": "bar",
-<lang Lisp>(let ((json-encoding-pretty-print t))
+   "baz": [
-  (json-encode example-object))</lang>
+,
-{{out}}
+,
-<pre>
-"{
-  \"list\": {
+   ]
+ }
-    \"cons\": [
-      [
-        \"quote\",
-        \"x\"
-      ],
-    ],
-    \"cons\": [
-      [
-        \"quote\",
-        \"y\"
-      ],
-      \"a string\"
-    ]
-  }
-}"
-</pre>
-===Encoding, with options===
-<lang Lisp>(let* ((json-encoding-pretty-print t)
-              (json-object-type 'alist)
-              (json-array-type 'vector)
-              (json-key-type 'symbol)
-	      (vec (make-vector 3 "element")))
-        (aset vec 1 "second")
-        (aset vec 2 -3)
-        (json-encode (list (cons 'x 2)
-                           (cons 'y "a string")
-                           (cons 'z vec))))</lang>
-{{out}}
-<pre>"{
-  \"x\": 2,
-  \"y\": \"a string\",
-  \"z\": [
-    \"element\",
-    \"second\",
-    -3
-  ]
-}"</pre>
 =={{header|Erlang}}==