@iterativeflow/mongodb

A MongoDB backend for iterativeflow — the four ports (Store / Queue / Timer / Wakeup) over one MongoClient. The transactional outbox commits across collections in a multi-document transaction, so the deployment must be a replica set (even a single-node one — MongoDB requires that for transactions). Passes the same conformance suites as the SQL and Redis backends.

import { MongoClient } from "mongodb";
import { createMongoBackend, ensureIndexes } from "@iterativeflow/mongodb";
import { createEngine } from "@iterativeflow/core";

const client = new MongoClient(process.env.MONGO_URL); // a replica-set connection string
await client.connect();
await ensureIndexes(client.db("iterativeflow"));
const engine = createEngine(createMongoBackend(client), [
  /* your flows */
]);

Notes

• mongodb is a peer dependency. Requires a replica set for transactions.
• Wakeup is in-process (like the SQL/Redis backends).
• Runs are documents keyed by _id = runId; steps/signals/jobs/timers/crons are their own collections. Cross-collection writers (the outbox) use a session transaction; single-document ops (claim, arriveAtJoin, …) use Mongo's per-document atomicity, no transaction needed.
• Run ensureIndexes(db, prefix?) once — the idempotency and signal-dedup indexes are partial (idempotency_key / idem_key $exists), so unkeyed docs never collide.