# protostuff/protostuff

Java serialization library, proto compiler, code generator

Repository: https://github.com/protostuff/protostuff
Canonical: https://ross.abutalabs.com/products/protostuff
Homepage: https://protostuff.github.io
Language: Java
License: Apache-2.0
License Family: permissive
Topics: protostuff, java, protobuf, serialization, json, graph
Last push: 2025-04-02T04:29:11+00:00

## Health v2 (maintenance only)
Score: 29/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 14, release rhythm 8, longevity 100
- inputs: {"age_days": 4609, "days_push": 518, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 2096, forks 303 (observed 2026-08-28T04:06:13.252199+00:00)

## What it is
Protostuff is a Java serialization library with built-in forward-backward compatibility (schema evolution) and validation, supporting pluggable formats like protobuf, JSON, and graph. It includes a proto compiler and code generator, and can serialize POJOs without pre-written schemas via runtime schema generation.

## Use cases
- serialize java objects to protobuf format
- replace java serialization with a faster binary format
- schema evolution for stored data with forward-backward compatibility
- efficient messaging format for rpc
- compact storage format for datastore or cache
- generate protobuf schemas from pojos at runtime
- convert objects to and from json

## When to choose
- you need efficient, memory-friendly binary serialization on the JVM
- you want protobuf compatibility without writing .proto files for existing POJOs
- your data schema evolves over time and you need compatibility across versions
- you need a fast messaging or cache storage format in Java

## When to avoid
- you need cross-language serialization with first-class support beyond the JVM
- your project is not on Java 1.6+ or the JVM ecosystem
- you need human-readable serialization as the primary format

## Facets
- artifact type: library
- maturity: active
- function: serialization, parser, json
- domain: developer-tools, backend, apis
- platform: jvm, cross-platform
- tags: protobuf, schema-evolution, code-generation, rpc, datastore

## Member repositories
- protostuff/protostuff (main) score 29

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:06:13.252199+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T02:54:37.911828+00:00, confidence not recorded.
  - readme: https://github.com/protostuff/protostuff (fetched 2026-08-28T04:06:13.252199+00:00, sha d9131eb2666e)
  - homepage: https://protostuff.github.io (fetched 2026-08-29T10:34:53.027085+00:00, sha 87bfa84de94a)
- Data as of 2026-08-30T08:39:29.467469+00:00.