I haven't kept track of FlatBuffers so I don't know what might have changed there, except that I imagine they support a lot more languages now (probably more th

I haven't kept track of FlatBuffers so I don't know what might have changed there, except that I imagine they support a lot more languages now (probably more than Cap'n Proto honestly). Cap'n Proto's serialization layer hasn't changed very much in those 5 years; development focus has been more on the RPC system.