Live Preview

const mounted = mountForm(container, {
  transport: createJsonTransport({ endpoint: "/api/predict" }),
  schema,
});

const unsubscribe = mounted.form.subscribeSelector(
  (state) => state.values,
  (values) => {
    preview.textContent = JSON.stringify(values, null, 2);
  },
  { emitInitial: true },
);

Use selector subscriptions for previews, summary panels, and analytics. Avoid expensive work on every keystroke; debounce in the host app when needed.