@fougere/schema

The entity and its 4 axes An entity declares fields; every field carries four independent axes — shape (which IS JSON Schema), role (primary, ref…), lifecycle (who writes the value, and when) and boundary (readOnly / writeOnly). Everything else in Fougere is a projection of them: tables, GraphQL types, form contracts, validation.

This package names no adapter and depends on no engine.

import { entity, primary, text, created, readOnly } from '@fougere/schema';

export default class Post extends entity({
  id: primary(),
  title: text(),
  authorId: readOnly(text()),
  createdAt: created(),
}) {}

Post.validate({ title: 'Bonjour' }); // → { success, data } | { success: false, errors }

It is a Standard Schema

Every entity — and every derivation of one — exposes ~standard, so it is accepted anywhere Standard Schema is, with no adapter package.

export class PostDraft extends Post.pick('title') {}

PostDraft['~standard'];
// → { version: 1, vendor: 'fougere', validate }

PostDraft['~standard'].validate({ title: '' });
// → { issues: [{ message: 'String is too short (0 < 1).', path: [{ key: 'title' }] }] }

Validation is synchronous, and the spec types are inlined rather than depended on, so this package stays zero-dependency.

One difference from most vendors, and it is deliberate: the judge does not fill defaults. A field declared bool({ default: false }) may be absent — that is legal, and the value comes back without the key. Filling belongs to the storage, at the point of persistence, so the same input judged twice never gains a field on the way through.

Installation

pnpm add @fougere/schema

Part of Fougere — one schema, a gradient from monolith to distributed, the same user code. Reference documentation: the site (en/fr).