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What is a background job queue (BullMQ/Redis) and when do you need one?

Q: What is a background job queue (BullMQ/Redis) and when do you need one?

**TL;DR.** A **job queue** stores units of work that **separate worker processes** consume asynchronously, with **retries, scheduling, and concurrency control**. Reach for one (e.g. **BullMQ** on Redis) to move **slow or unreliable** work — emails, image processing, webhooks, reports — **out of the request path**, so responses stay fast. API (producer) add(job) queue Redis <path class='d-edge

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Understand the problem

Offloading slow/async work to durable queues.

nodejsqueuebullmqredisasync

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Enqueue + process with BullMQ

import { Queue, Worker } from 'bullmq';
const connection = { host: 'localhost', port: 6379 };

const emails = new Queue('emails', { connection });
// In the request: return fast, do work later
await emails.add('welcome', { to: user.email }, { attempts: 3, backoff: { type: 'exponential', delay: 1000 } });

// Separate worker process:
new Worker('emails', async (job) => sendEmail(job.data), { connection, concurrency: 5 });

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