Make sure to never send Symbol objects to Oj, it will serialize them as ":foo". All other JSON libraries will represent them as "foo". And if you need to traver

Make sure to never send Symbol objects to Oj, it will serialize them as ":foo". All other JSON libraries will represent them as "foo". And if you need to traverse your object graph to call #to_s on the symbols then the performance gain of Oj is lost.