@langgraph-toolkit/adapter-checkpointers

Choose persistence without changing graph code. This package implements the Core checkpoint contract and provides a small Persistence facade over injected SQL, Redis, MongoDB, or in-memory drivers.

Install when the graph needs durable state

npm install @langgraph-toolkit/core @langgraph-toolkit/adapter-checkpointers

Configure persistence while composing the resource. Normal graph calls still receive business input. A resume call adds only the thread identifier and the interrupt response required by the graph.

import { createPersistence } from "@langgraph-toolkit/adapter-checkpointers";

const persistence = createPersistence();

await persistence.snapshot({
  threadId: "conversation-1",
  snapshotId: "snapshot-1",
  state: { question: "count users", answer: "6" },
  node: "answer",
  round: 2,
  createdAt: Date.now(),
});

const latest = await persistence.restore<{ question: string; answer: string }>({
  threadId: "conversation-1",
});

The default is an in-memory implementation for local development and tests: createMemoryCheckpointer (also available as autoCheckpoint()) is re-exported from @langgraph-toolkit/core, which owns the single canonical implementation. It orders checkpoint lookup by insertion rather than timestamp, so same-millisecond checkpoints never return a stale record on resume. Production applications inject a driver-backed checkpointer through createPersistence({ checkpointer }).

Redis convenience

useRedis() keeps the common Redis path short while still allowing the application to inject its own five-command client. No Redis SDK is bundled or forced on the application.

import { useRedis } from "@langgraph-toolkit/adapter-checkpointers";

const persistence = useRedis({
  driver: redisDriver,
  prefix: "app:graph:",
  ttlSeconds: 86_400,
});

The facade exposes snapshot, restore, history, and fork. fork() creates a new thread and snapshot identifier without mutating the source snapshot.

Lower-level drivers

| Backend | Public surface | Application responsibility | |---|---|---| | SQLite, PostgreSQL, MySQL | SqlCheckpointer, syncSqlDriver | Client, pool, migrations and credentials | | Redis | RedisCheckpointer, useRedis | Five-command driver, key namespace and TTL | | MongoDB | MongoCheckpointer | Collection, indexes, client and credentials | | Local tests | createPersistence() | No external dependency |

The graph imports only Core contracts. It does not import a database client, know a table schema, or receive a checkpointer on every request.

Development

npm install
npm run build
npm test

Tests use deterministic injected drivers and do not require a live external database.

License

MIT