2026Systems
guts
Schema validation for Node.js, compiled to native Rust.
A structural schema validation library with a fluent, Zod-like JavaScript API and a native Rust engine behind it. Schemas compile once into Rust enum blueprints, so hot paths skip JavaScript parsing entirely. Published on npm as guts-validator.
How it works
1
Compile once, validate fast
Schema shapes become optimised Rust variants at instantiation, avoiding the V8 JIT bailouts and GC churn of tree-walking validators.
2
Streaming AI output
Validates incomplete JSON chunks from LLM streams, repairing missing closing syntax on the fly instead of crashing mid-stream.
3
Coercion and precise errors
Coerces stringified numbers and booleans inside native loops, and reports nested paths like routing.table.0.gateway.
Built with
Rust
NAPI-RS
Node.js
TypeScript