> These two are not analogous. Writing your own JSON deserializer/serializer can absolutely make sense depending on what you are doing. You'd better have a very

> These two are not analogous. Writing your own JSON deserializer/serializer can absolutely make sense depending on what you are doing. You'd better have a very good reason for writing your own sha algorithm. I mostly agree with you, but to me this is presented as a logically-inconsistent argument. Why is writing my own JSON serializer relatively better than writing my own SHA implementation? Don't we first need to look at the actual problem? Why does it have to be a very good reason, as opposed to simply the same quality of reasoning used for the JSON decision?