capnproto/capnproto-rust

Health v2 · maintenance only

Flags: no_releases

Adoption not part of the score

2497 stars · 262 forks observed · 2026-08-28

What it is AI-extracted, prompt v1, taxonomy v1, 2026-08-30, confidence not recorded

A Rust implementation of the Cap'n Proto data serialization format and RPC protocol. It generates code from schema files enabling zero-copy message reading and building, with support for tagged unions, generics, protocol evolution, and no_std/no-alloc environments.

Use cases

• serialize structured data in Rust without deserialization overhead
• define RPC interfaces between distributed services
• exchange messages between Rust and other Cap'n Proto languages
• persist data to disk in a fast binary format
• build embedded Rust software with no_std serialization

When to choose

• you need extremely fast serialization with zero-copy reads
• you want schema-driven RPC across multiple languages
• you target embedded or no_std Rust environments

When to avoid

• you need human-readable formats like JSON
• your ecosystem already standardizes on Protocol Buffers or gRPC
• you only need simple ad-hoc data exchange

Facets

library · maturity active

serialization rpc parser microservices apis developer-tools rust cross-platform embedded capn-proto zero-copy schema-codegen no-std

Member repositories

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