# Redis Bullmq Systems

> Review Redis and BullMQ job systems for throughput, retries, idempotency, deduplication, queue isolation, failure recovery, and backlog health.

- **Type:** Skill
- **Install:** `agentstack add skill-caiaffa-claude-code-ultimate-engineering-system-redis-bullmq-systems`
- **Verified:** Yes — security-reviewed for prompt injection and unsafe behavior
- **Seller:** [caiaffa](https://agentstack.voostack.com/s/caiaffa)
- **Installs:** 0
- **Category:** [Databases](https://agentstack.voostack.com/c/databases)
- **Latest version:** 0.1.0
- **License:** MIT
- **Upstream author:** [caiaffa](https://github.com/caiaffa)
- **Source:** https://github.com/caiaffa/claude-code-ultimate-engineering-system/tree/main/skills/redis-bullmq-systems

## Install

```sh
agentstack add skill-caiaffa-claude-code-ultimate-engineering-system-redis-bullmq-systems
```

Requires the [AgentStack CLI](https://agentstack.voostack.com/docs/cli). Works with Claude Code, Cursor, and any MCP-compatible agent.

## About

# Mission
Make asynchronous job systems predictable, debuggable, and safe under retries, backlogs, partial failures, and restarts.

# When to use
- Designing workers or queues.
- Reviewing BullMQ processing logic.
- Investigating job duplication, lag, or stuck jobs.
- Tuning throughput and concurrency.

# Handoff
- **Receives from:** backend-platform-engineer (implementation).
- **Hands off to:** otel-observability-architect (queue telemetry), premortem-facilitator (pre-launch), release-commander (deploy).

# BullMQ reality check
- BullMQ is **at-least-once**, never exactly-once. Design for it.
- Jobs can be delivered **more than once** after crashes, timeouts, or Redis failovers.
- Job completion ≠ side-effect completion (DB write may succeed but ack may fail).
- Repeated jobs (cron/schedulers) can **overlap** if previous run is still active.

# Design checklist
1. **Idempotency** — where is the dedup boundary? (database unique constraint? Redis SET NX? application check?)
2. **Retry policy** — which errors are retryable? what's the backoff? what's the max attempts? what happens at max?
3. **Dead letter** — where do permanently failed jobs go? who monitors? who resolves?
4. **Concurrency** — what's the per-worker concurrency? what happens at 2x/10x job volume?
5. **Queue isolation** — are noisy/slow job types separated from critical ones?
6. **Graceful shutdown** — does the worker finish in-progress jobs before exit? timeout?
7. **Stuck jobs** — how are stalled jobs detected and recovered? `stalledInterval` configured?
8. **Backlog** — what metrics show queue depth, age, and processing latency?

# Common failure patterns
| Pattern | What goes wrong | Fix |
|---|---|---|
| No idempotency key | Retry creates duplicate business effects | Dedup at DB or application level |
| Unbounded retries | Poison job retried forever, blocks queue | Max attempts + dead letter |
| Shared queue for all job types | Slow bulk job starves time-sensitive jobs | Separate queues per priority/type |
| No stalled job detection | Worker crash leaves job in "active" forever | Configure `stalledInterval` + `maxStalledCount` |
| Cron overlap | Previous run still active when next starts | Mutex lock or `jobId`-based dedup |
| No backlog alerting | Queue grows for hours before anyone notices | Alert on queue depth + oldest job age |

# Output format
1. **Queue architecture summary**
2. **Failure mode analysis** (per job type)
3. **Idempotency assessment** (where is it? where is it missing?)
4. **Throughput/concurrency bottlenecks**
5. **Monitoring recommendations** (specific metrics + alert thresholds)

## Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

- **Author:** [caiaffa](https://github.com/caiaffa)
- **Source:** [caiaffa/claude-code-ultimate-engineering-system](https://github.com/caiaffa/claude-code-ultimate-engineering-system)
- **License:** MIT

Install and usage instructions live in the source repository linked above.

## Pricing

- **Free** — Free

## Security capabilities

Automated source analysis of v0.1.0 — what this tool can access:

- **Network access:** no
- **Filesystem access:** no
- **Shell / process execution:** no
- **Environment & secrets:** no
- **Dynamic code execution:** no

*"Yes" means the capability is present in the source — more access means more to trust, not that it is unsafe.*


## Versions

- **0.1.0** — security scan: passed — Imported from the upstream source.

## Links

- Listing page: https://agentstack.voostack.com/l/skill-caiaffa-claude-code-ultimate-engineering-system-redis-bullmq-systems
- Seller: https://agentstack.voostack.com/s/caiaffa
- Browse the marketplace: https://agentstack.voostack.com/browse

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Listed on AgentStack — the marketplace for AI agent skills and MCP servers. Every listing is security-reviewed. Creators keep 70%.