I would suggest the author also look at Amazon Ion: * It can be used as schema-less * allows attaching metadata tags to values (which can serve as type hints[

I would suggest the author also look at Amazon Ion: * It can be used as schema-less * allows attaching metadata tags to values (which can serve as type hints[1]), and * encodes blobs efficiently I have not used it, but in the space of flexible formats it appears to have other interesting properties. For instance it can encode a symbol table making symbols really compact in the rest of the message. Symbol tables can be shared out of band. [1] https://amazon-ion.github.io/ion-docs/docs/spec.html#annot https://amazon-ion.github.io/ion-docs/docs/spec.html#annot