Rust

Rust serialization is dominated by the serde data model: libraries implement Serialize/Deserialize once, then plug in format backends. A second tier (rkyv, FlatBuffers, Cap’n Proto) targets zero-copy access.

Benchmark runner

• Directory: rust/ (repository root)
• Output: monorepo logs/rust/YYYY-MM-DD-HHMMSS.csv (Language=rust, times in nanoseconds)
• Runner: rust/scripts/run-benchmarks.sh {smoke|all-single|full|research} or cargo run --release -- <reps>
• Registration: rust/src/serializers/mod.rs (family modules under serializers/)

Serializers

Serializer	Category	Crate	Native path	Stream	Notes
bincode	Binary	bincode 2	Serde; config in prepare	adapted	Config not rebuilt per call
bitcode	Binary	bitcode	Serde	adapted	Bit-packed
bson	Document	bson	Serde	adapted	Document DB interop
ciborium	CBOR	ciborium	Serde	native	Reused write buffer
flexbuffers	FlexBuffers	flexbuffers	Serde	adapted	Schemaless FB family
minicbor	CBOR	minicbor	Direct Encode/Decode on structs	adapted	No MessagePack envelope
nanoserde	Binary	nanoserde	SerBin/DeBin	adapted	Zero-dep style binary
postcard	Binary	postcard	Serde	adapted	no_std-friendly format
prost	Schema	prost + build	Protobuf messages in prepare	adapted	De-facto Rust Protobuf (no Google-owned Rust runtime; prost-build + fixture/shared protos)
rkyv	Zero-copy	rkyv 0.8	Full Archive on structs	adapted	Timed deser materializes owned T for fidelity
rmp-serde	MessagePack	rmp-serde	to_vec_named	adapted	Named maps
serde_avro_fast	Schema	serde_avro_fast	Serde one-pass datum; reused SerializerConfig	native	Prefer over official apache-avro (Value intermediate is multi-× slower than JSON on small records)
serde_json	JSON	serde_json	Serde Fixture	native	Baseline
simd-json	JSON	simd-json	SIMD parse; ser via serde_json	adapted	Honest split responsibilities
sonic-rs	JSON	sonic-rs	Serde-compatible SIMD JSON	adapted	Hot-path JSON
speedy	Binary	speedy	Writable/Readable	adapted	Fast binary framework

Call-path contract (same idea as Python)

prepare(fixture)                 # untimed: config, kind, prost convert
for rep:
  serialize_bytes / stream       # timed
  deserialize_bytes / stream     # timed
  fidelity(expected, actual)     # untimed

Caveats

• simd-json serialize is serde_json (crate optimizes parse).
• rkyv: access-only (zero-copy without materialize) would be faster; suite materializes for a fair owned-value fidelity check.
• prost date fields may use millisecond timestamps; fidelity allows limited date-string drift where configured.
• flatbuffers / capnp: not registered yet (codegen weight); flexbuffers partially covers FB-family schemaless use.
• Stream mode is native only where noted; others are adapted bytes+cursor.

Also: rust/README.md. Serialization Categories.

Design choices

1. Prepare outside the loop — configs, buffers, prost messages, kind tags.
2. Optimal APIs — crate-recommended encode/decode; no pretty-print.
3. Dual mode — bytes and stream with StreamMode metadata.
4. Concrete types for non-Serde stacks (minicbor, rkyv, nanoserde, speedy, prost).