Cap'n Proto
Cap'n Proto is a zero-copy serialization format designed by Kenton Varda: the in-memory layout of data is the wire format, so no encoding/decoding step exists.
Purpose
It eliminates serialization overhead in extremely low-latency scenarios by reading and writing memory-mapped regions directly.
Mechanism
Structured data is laid out as pointers and fixed-width fields in contiguous memory, and the wire format equals the memory layout. Readers traverse pointers without decoding.
Use cases
- Low-latency RPC
- Real-time game communication
- High-performance IPC