@orkestrel/contract

The zero-dependency contract toolkit — runtime type guards, guard combinators, coerce-and-extract parsers, and a shape DSL that compiles once into a guard, parser, fault report, JSON Schema, and generator that can never drift. The foundation package of the @orkestrel line.

Install

npm install @orkestrel/contract

Requirements

• Node.js >= 22.12
• TypeScript-first (ships its own .d.ts types)

Usage

import {
	createContract,
	integerShape,
	objectShape,
	seededRandom,
	stringShape,
} from '@orkestrel/contract'

const user = createContract(
	objectShape({
		name: stringShape({ min: 1 }),
		age: integerShape({ min: 0, max: 120 }),
	}),
)

user.is({ name: 'Ada', age: 36 }) // true
user.parse({ name: 'Ada', age: '36' }) // { name: 'Ada', age: 36 } — coerces, or undefined
user.explain({ name: '', age: 36 }) // [{ reason: 'constraint', path: ['name'], constraint: 'min', limit: 1, … }]
user.schema // the owned, deeply frozen compiled JSON Schema
user.generate(seededRandom(42)) // reproducible seed data; omit the arg for a wall-clock-seeded source

Guide

For the full surface — guards, combinators, parsers, the JSON boundary, and the shape DSL — see guides/src/contract.md.

Package

Published as a single typed entry point per the exports field in package.json.

License

MIT © Orkestrel — see LICENSE.