@sometic/store-immer

Optional Immer adapter that adds draft-style produce updates to Sometic stores.

@sometic/store-immer exports createImmerStore, a thin wrapper around createStore from @sometic/store. You keep the same get, set, update, batch, subscribe, and dispose API, plus produce(updater) that runs Immer’s produce against the current state and commits the next immutable snapshot.

Sometic keeps the core store free of Immer so most apps never pay for draft machinery. This package exists for teams that prefer mutable-looking updates for nested objects while still shipping portable, framework-independent store behavior. It is an opt-in peer layer, not a second state system.

Out of the box you get typed ImmerUpdater drafts, full DisposableStore compatibility, and the same CreateStoreOptions (including custom equality) as the base store. There is no persistence or cross-tab logic here: compose with @sometic/store/persistent and related subpaths when you need those features on a plain store, or wrap only the in-memory slice that benefits from Immer.

In the ecosystem, install this only when Immer is already (or will be) a peer in your app. It sits beside @sometic/store and ultimately @sometic/core. Theme, auth, and forms do not require it. Product context: https://sometic.dev/guide/introduction.

Install

pnpm add @sometic/store-immer @sometic/store immer

npm install @sometic/store-immer @sometic/store immer

yarn add @sometic/store-immer @sometic/store immer

Usage

Draft updates with produce:

import { createImmerStore } from "@sometic/store-immer";

type TodoState = {
    items: Array<{ id: string; done: boolean }>;
};

const store = createImmerStore<TodoState>({
    items: [{ id: "1", done: false }],
});

store.produce((draft) => {
    const first = draft.items[0];
    if (first) {
        first.done = true;
    }
});

console.log(store.get().items[0]?.done);

Same subscription surface as @sometic/store:

import { createImmerStore } from "@sometic/store-immer";

const store = createImmerStore({ nested: { count: 0 } });

const unsubscribe = store.subscribe((state, previous) => {
    console.log(previous.nested.count, "->", state.nested.count);
});

store.produce((draft) => {
    draft.nested.count += 1;
});

unsubscribe();
store.dispose();

Peers / when not to use

Peer dependencies: @sometic/store (>=1.0.0) and immer (^10). Skip this package when immutable update spreads are enough, when bundle size is tight, or when you do not want Immer in the dependency graph. Prefer plain @sometic/store for most Sometic integrations.

Docs

• Introduction: https://sometic.dev/guide/introduction
• Immer adapter: https://sometic.dev/stores/store-immer
• Store: https://sometic.dev/stores/store
• Core on npm: https://www.npmjs.com/package/@sometic/core
• Store-immer on npm: https://www.npmjs.com/package/@sometic/store-immer

License

MIT