Hmm, not sure I exactly understand the question. But I think the answer is probably "no". Cap'n Proto's design came mostly out of someone asking me one day whether two processes could share a protobuf object via shared memory, without serializing and parsing. I found the question interesting enough that I kept thinking about it and that eventually evolved into a design. My reasons for leaving Google had nothing to do with any of this, but gave me a well-timed opportunity to work on it.

I actually primarily quit to do sandstorm.io, and did Cap'n Proto more on a lark, although it turns out to be really useful infrastructure on which to build Sandstorm.