Upgrading to 0.8.0

Version 0.8.0 adds observable history and persistence status and simplifies the public API. This pre-1.0 release includes breaking changes for consumers of 0.7.x.

Required updates

Previous usage	Use in 0.8.0
persistence.unsubscribe()	persistence.dispose()
Import prepareStoreForHydration from /react	Import it from @codebelt/classy-store/react/server, on both server and client
Import getVersion from the root entry	Use subscribe() for notifications or compare snapshot() references
Assume explicit persistence calls always resolve	Handle rejected promises from save(), clear(), and rehydrate()
Transform a property's value as a union of all store properties	Match serialize and deserialize to the property selected by key

Dispose persistence handles

Update effect cleanups and other teardown calls:

// Before
return () => persistence.unsubscribe();

// After
return () => persistence.dispose();

Disposal is idempotent. It stops subscriptions and timers, ignores pending read results, and cancels writes that have not started. Already-issued storage I/O cannot be cancelled. Explicit queued operations cancelled by disposal reject, as do explicit operations called after disposal.

Handle explicit persistence failures

save(), clear(), and rehydrate() take no options. They report storage failures through onError and lastError, and reject their promises. Handle the promise even when an onError callback is configured:

try {
  await persistence.save();
  showSavedMessage();
} catch (error) {
  showSaveError(error);
}

Automatic writes and initial hydration handle reported failures internally. hydrated resolves once an attempt settles; isHydrated also means an attempt settled, including failure or a superseded read. Both stay settled during later reads; await rehydrate() for a specific new attempt. Check persistence.getSnapshot().lastError when the result matters. A failed operation does not prevent later queued writes from running.

Subscribe to utility status in React

Use useClassyStore(store) for store data. Use the new hooks when rendering utility metadata that can change independently of that data:

import {useHistoryStatus, usePersistStatus} from '@codebelt/classy-store/react';

const {canUndo, canRedo, isPaused} = useHistoryStatus(history);
const {isHydrated, isExpired, lastError} = usePersistStatus(persistence);

Call these hooks inside a component or custom hook, with stable handles. Both status snapshots include isDisposed. History pause state now stays consistent when undo/redo finishes.

Outside React, handles expose getSnapshot(), getServerSnapshot(), and subscribe(listener). The function returned by subscribe removes that status listener; dispose() tears down the utility handle itself. The shared status source implementation is internal. Consumer types are HistoryHandle, HistoryStatus, PersistHandle, and PersistStatus, exported from @codebelt/classy-store/utils.

During SSR and hydration, status hooks use the handle's initial status snapshot. Construct server and client handles with matching initial status.

Use the hydration entry on server and client

import {prepareStoreForHydration} from '@codebelt/classy-store/react/server';

The /react entry exports React hooks and createStoreHook. Hydration preparation is exported only from /react/server; its captured-snapshot behavior is unchanged.

Match persistence transforms to their property

Transform serializers receive the selected property's readonly snapshot value. Deserializers receive unknown and must return that property's mutable value. Validate stored values before returning them. Transforms that mutate their snapshot input or return another property's type now fail TypeScript checks.

Persistence status flags are readonly, matching their runtime getters. PersistOperation is exported from the utilities entry for typed error handlers.

If upgrading from 0.6.x or earlier, also follow the 0.7.0 upgrade guide for React timing options and the native WeakRef requirement.