There are too many factors to make a broad comparison in milliseconds. Are you running the code on a RaspPi or on the latest Zen3? Serialization should be impl

There are too many factors to make a broad comparison in milliseconds. Are you running the code on a RaspPi or on the latest Zen3? Serialization should be implemented in C so unless the JSON is megabytes in size, whatever is happening here probably has to do with the business logic implemented in Python. Python and Ruby are equally slow when they aren't wrapping frameworks primarily written in C (e.g. tensorflow), so choosing between them is IMO a stylistic or compatibility choice.