I know this isn't new, but I wonder if the name is an intentional nod to Star Trek Voyager or is there another reference I'm not aware of.
The name Cap'n Proto actually originally meant "Capabilities and Protobufs" -- it was a capability-based RPC protocol based on Protocol Buffers. However, early on I decided I wanted to try a whole different serialization format instead. "Proto" still makes sense, since it is a protocol, so I kept the name.
The pun "cerealization protocol" is actually something someone else had to point out to me, but I promptly added it to the logo. :)
https://en.wikipedia.org/wiki/Capability-based_security
https://capnproto.org/rpc.html#distributed-objects
The idea really goes way beyond security and RPC. It's hard to explain concisely but it's sort of a way of thinking about software architecture.