HiBON

HiBON the Hash invariant Binary Oobject Notation is the one and only data exchange format used in the core system. Not only is it fast, allowing for efficient data transfer. It most importantly because of its hash-invariance makes it trivial to sign data.

The specification can be found at https://www.hibon.org,
it also includes specifications for converting between a json compatible format, rpc structure, record types for validation for easy type validation.