OIMDB

A high-performance, event-driven in-memory database designed specifically for frontend applications. OIMDB provides reactive collections, intelligent indexing, and configurable event processing for building fast, predictable state management solutions.

Packages

OIMDB is organized as a monorepo with separate npm packages:

Package	Description
@oimdb/core	Reactive collections, indexes, event queue, selectors
@oimdb/react	React hooks and context provider
@oimdb/redux-adapter	Redux reducers backed by OIMDB, two-way sync
@oimdb/async	Async collections and indexes
@oimdb/persist	Storage-agnostic persistence engine for collections, objects, indexes; onHydrate/byPk hydration-merge
@oimdb/persist-memory	Persist backend: in-memory Map (tests, SSR)
@oimdb/persist-localstorage	Persist backend: localStorage
@oimdb/persist-idb	Persist backend: IndexedDB
@oimdb/persist-json	Persist backend: JSON dump for SSR dehydrate/hydrate
@oimdb/persist-async-kv	Persist backend: async key-value — React Native AsyncStorage, Cordova
@oimdb/snapshot-manager	Track and snapshot cross-collection changes

Key Benefits

• Performance first — Map-based storage with O(1) lookups
• Reactive architecture — Key-scoped subscriptions with intelligent coalescing
• Type safety — Full TypeScript support with advanced generics
• Configurable — Multiple scheduler options for different use cases
• Modular — Use only what you need, extend what you want

Quick Example

import {
  createOIMCollectionKit,
  OIMEventQueue,
  OIMEventQueueSchedulerFactory,
} from '@oimdb/core';

interface User {
  id: string;
  name: string;
  email: string;
  teamId: string;
}

const queue = new OIMEventQueue({
  scheduler: OIMEventQueueSchedulerFactory.createMicrotask(),
});

const users = createOIMCollectionKit<User, string>(queue, {
  selectPk: (user) => user.id,
});
const usersByTeam = users.indexFactory.derivedSetIndex((user) => user.teamId);
const teamUsers = users.select.entitiesBySetIndexKey(usersByTeam, 'team1');

users.collection.updateEventEmitter.subscribeOnKey('user1', () => {
  console.log('User1 updated!');
});

const userSlot = users.collection.upsertOne({
  id: 'user1',
  name: 'John',
  email: 'john@example.com',
  teamId: 'team1',
});

const updatedUserSlot = users.collection.upsertOne({
  id: 'user1',
  name: 'John Doe',
  email: 'john@example.com',
  teamId: 'team1',
});

console.log(userSlot === updatedUserSlot); // true
teamUsers.watch((value) => console.log(value));
// Only one notification fires due to intelligent coalescing

Next Steps

• Installation — install the packages you need
• Quick Start — build your first reactive schema
• Core Model — collections, slots, indexes, and selectors
• Indexes and Selectors — derived indexes, manual indexes, and selector DX
• Performance Guide — benchmarks and optimization strategies