Behavior in the engine
Typed state, validation, arrays, drafts, history and submission are independent of the rendering layer.
Typed form engine for TypeScript
One form contract. Every framework. Any backend.
The typed contract between your backend and every frontend form. State, validation, drafts and submission live in a framework-independent engine; the form itself can travel as data.
npm i @modyra/core
- Framework-free
- React
- Preact
- Solid
- Vue
- Svelte
- Angular
- Lit
- Zod
- Standard Schema
- Rust & Java SDKs
Sixty seconds
One contract, running
Not another form state hook
A form contract
A hook keeps form logic in your components. A contract takes it out: one validated document any renderer can run, and any backend — Rust, Java, or a visual builder — can produce.
// contract.json — from a service, a CMS, Studio, or a model
[
{ "name": "email", "kind": "text", "label": "Email",
"validators": { "required": true, "email": true } },
{ "name": "country", "kind": "select", "label": "Country",
"options": [{ "value": "IT", "label": "Italy" }] }
]
import { parseDynamicForm } from "@modyra/core";
const doc = parseDynamicForm(contract, { mode: "strict" });
if (!doc.ok) return report(doc.diagnostics);
mountMdyForm(host, doc.fields, doc); // framework-free
const form = useMdyDynamicForm(doc.fields); // React
// <mdy-dynamic-form [fields]="doc.fields" /> — AngularForms as data
Safe enough for strangers — and agents
A contract that arrives over a network is untrusted input, and Modyra parses it that way: a bounded set of kinds, validators, layout nodes and rule operators, rejected or reported before anything renders. That is the boundary an LLM or an agent runtime needs when the form it emits must validate, cancel safely and never execute.
Design
One model, explicit boundaries
Rendering is optional
Use the framework-free renderer, connect a framework adapter, or keep the form in a server, worker or test.
Limits stay visible
Adapters differ in UI coverage, SSR behavior and integration depth. Those differences are documented rather than hidden.
The honest part
When Modyra is the wrong tool
One login form in one React app? react-hook-form is the lighter, safer pick. Modyra pays off when the same form must live in more than one application — or arrive from somewhere you do not control.
The engine measures 26.7 KB gzipped on a realistic typed form with arrays, validation, drafts and undo (core 2.4.0, measured 2026-08-21; reproduce with npm run test:core-bundle). That is the heaviest entry in our own comparison — it is what drafts, cancellation and undo cost when you stop maintaining them yourself.
Continue
Start from the layer you need
Understand the engineState, handles, operations and lifecycle.Choose a rendering modeTyped, headless, framework-free or data-driven.Explore StudioAuthor, validate, preview and export a form model.
@modyra/core 2.4.0 ·MIT licensed · eight adapters, two schema adapters, two backend SDKs · engine and widget contract at 2.4.0; adapters, SDKs and Studio below 1.0