Narro

Lightweight TypeScript schema validation library with a Zod-like API that keeps bundle sizes minimal.

⚠️ Development Status: Narro is in early development with no stable release yet. The API may change in future builds.

Why Narro

• Tiny bundles – constraint logic lazy-loads on first build, so unused checks never ship
• Zod-like API – familiar, chainable schema composition
• Heuristic insights – built-in scoring highlights the most plausible schema branch and pinpoints failures
• Performance options – choose between minimal bundles or maximum throughput

Runtime Modes

• safeParse (lazy) – validates with dynamic imports for minimal bundles
• build() (eager) – preload checks upfront for reuse in hot paths
• narro/inline – all checks bundled together for maximum throughput

Quick Start

import * as n from 'narro'

const ageSchema = n.number().min(0).max(130)
const report = await ageSchema.safeParse(input)

if (report.success) {
  // use report.value
}
else {
  // see why validation failed
}

Project Structure

This is a monorepo containing:

• packages/narro – the main validation library
• packages/bench – performance benchmarks

Development

# Install dependencies
pnpm install

# Run tests
pnpm -r test

# Lint
pnpm lint

# Release narro package
pnpm release:narro

License

MIT