facet-rs/facet

Health v2 · maintenance only

Adoption not part of the score

2570 stars · 128 forks observed · 2026-08-28

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

Facet is a Rust reflection ecosystem: a single derive macro gives types a runtime SHAPE description (fields, variants, attributes, layout) that other crates consume. On top of that core it provides serialization/deserialization for JSON, TOML, YAML, MessagePack, CSV, XML and more, plus pretty-printing, diffing, and introspection tooling.

Use cases

• serialize rust structs to json without serde
• reflect on struct fields at runtime in rust
• pretty-print rust values with sensitive field redaction
• generate schemas from rust types
• diff two rust structs structurally
• deserialize config files into typed rust structs
• introspect type metadata via a derive macro

When to choose

• you want one derive to power serialization, introspection, diffing, and pretty-printing instead of separate serde/other derives
• you need runtime access to type structure (fields, attributes, invariants) in Rust
• you want span-aware serialization errors or sensitive-field redaction

When to avoid

• you need the mature, battle-tested serde ecosystem with maximal format and community support
• your project requires stable 1.0 APIs — facet is still pre-1.0 and evolving
• you only need basic JSON serialization and already use serde

Facets

library · maturity active

serialization parser developer-tools plugin-system developer-tools programming-languages apis rust cross-platform reflection proc-macro introspection type-shape serde-alternative pretty-printing schema-generation structural-diffing

Member repositories

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