[kevincox]

You seem to be assuming that a JSON object is a "struct" with a fixed set of application-defined keys. Very often it can also be used as a "map". So the number of keys is essentially unbounded and just depends on the size of the data.

[mpweiher]

Erm, yes, structs seems to be the use-case this is consciously and very deliberately aiming at:

SICK: Streams of Independent Constant Keys

And "maps" seems to be a use case it is deliberately not aiming at.

[zamadatix]

Isn't the example in the readme just a smaller map style object instead off a larger one?