Today I discovered [1] there's also Flatbuffers. And SBE (Simple Binary Encoding) [2]. [1] https://viewer.scuttlebot.io/%25%2F7Lt3l6yFO5uPofcn%2FGErykgvoR%2FLcuZEZgsCqyfS9E%3D.sha256 [2] https://capnproto.org/news/2014-06-17-capnproto-flatbuffers-sbe.html