Smile Data Format
"Smile" is a binary data format that defines a binary equivalent of standard JSON data format.
Format was specified in 2010 by Jackson JSON processor development team. First compliant implementation was Jackson 1.6, released in September 2010.
Specification
Design documentation includes:
Format specification describes format itself; how it works and what a compliant parser/generator implementations needs to do.
Design goals explains rationale for design decisions concerning specification.
Community
Jackson developer mailing list is also a good resource regarding the first complete Java-based implementation
Documentation
Implementations, frameworks that support Smile
Jackson JSON processor has full Smile support, including streaming access, data binding and tree model (i.e. parity with textual JSON)
libsmile is a work-in-progress C-library for reading and writing Smile data.
Elastic Search supports Smile as one of input/output formats
Protostuff project supports Smile both as a low-level data format, and as format used for RPC.