See expm homepage for jsonex.
$ mix run 'IO.puts Jsonex.encode([a: 1, b: 2])'
{"a":1,"b":2}
mix run 'IO.inspect Jsonex.decode("{\"a\": 1, \"b\": 2}")'
[{"a",1},{"b",2}]
This software is under the Apache 2 License. See the LICENSE file for more details.