---
title: Memory
description: In-memory state adapter for development and testing.
tagline: In-memory state adapter for local development and tests. State is lost on restart and locks don't work across instances, so don't use it in production.
package: @chat-adapter/state-memory
---

# Memory



## Install

<PackageInstall package="@chat-adapter/state-memory" />

## Quick start

```typescript title="lib/bot.ts" lineNumbers
import { Chat } from "chat";
import { createMemoryState } from "@chat-adapter/state-memory";

const bot = new Chat({
  userName: "mybot",
  adapters: { /* ... */ },
  state: createMemoryState(),
});
```

`createMemoryState()` takes no arguments. Subscriptions, locks, cache entries, lists, and queues live in the current process and disappear when the process exits.

Use it for local development and for tests that need a real `StateAdapter` without a Redis or Postgres dependency.

## Limitations

Everything the adapter stores lives in one process's memory. In production, that leads to these problems:

* State doesn't survive a restart or redeploy. Thread subscriptions, thread state from `setState()`, and queued messages are lost, so new messages in previously subscribed threads no longer reach `onSubscribedMessage`.
* State isn't shared between instances. A thread subscribed on one instance looks unsubscribed on another, and deduplication only catches repeat deliveries that reach the same instance.
* Locks only apply within one process. Two instances can acquire the lock for the same thread and handle messages in it at the same time.

When `NODE_ENV` is `production`, `connect()` logs a warning that the memory adapter isn't recommended for production. For production, use [`@chat-adapter/state-redis`](/adapters/official/redis), [`@chat-adapter/state-ioredis`](/adapters/official/ioredis), or [`@chat-adapter/state-pg`](/adapters/official/postgres).

## Feature support

<FeatureSupport />