State

Persistence

State stays in memory by default. To persist it, explicitly choose session storage or local storage; Demetria versions and validates its saved snapshot.

Storage option

createForm({
  target,
  schema,
  persistence: {
    type: 'sessionStorage',
    key: 'demetria:signup'
  }
});

Supported types are sessionStorage and localStorage. The versioned snapshot contains schema identity, the current step, and form values. Invalid, incompatible, or unavailable stored state is ignored and reported through getState().persistenceStatus.

Demetria saves after value changes and successful step transitions, including completion. It does not expire or clear stored state automatically; an application can remove its known storage key when the flow is complete.

Real page-to-page flow

Use the same schema and persistence configuration on each document. Set its initial step for the current document and navigate from onStepChange. The multi-page example demonstrates this using window.location.assign, so Next changes documents rather than swapping a form in place.

Security and privacy

• Treat restored data as untrusted input.
• Use a namespaced key and remove it when the flow is complete.
• Prefer sessionStorage for short-lived examples; choose storage based on your threat model.
• Always validate and authorize submitted values on the server.