Redis Patterns

Quick Guide: Use Redis as an in-memory data store for caching, session management, rate limiting, pub/sub messaging, and job queues. Use ioredis (v5.x) as the primary client for its superior TypeScript support, Cluster/Sentinel integration, auto-pipelining, and Lua scripting. Use node-redis (v5.x) only when you need Redis Stack modules (JSON, Search, TimeSeries). Always set maxRetriesPerRequest: null for BullMQ workers, use separate connections for Pub/Sub subscribers, and define Lua scripts via defineCommand for atomic multi-step operations.

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CRITICAL: Before Using This Skill

All code must follow project conventions in CLAUDE.md (kebab-case, named exports, import ordering, import type, named constants)

(You MUST use a SEPARATE Redis connection for Pub/Sub subscribers -- a subscribed connection enters a special mode and cannot execute other commands)

(You MUST set maxRetriesPerRequest: null on any ioredis connection passed to BullMQ -- BullMQ requires infinite retries and will throw if this is not set)

(You MUST use Lua scripts (defineCommand or eval) for any operation requiring atomicity across multiple Redis commands -- separate commands are NOT atomic even in a pipeline)

(You MUST handle the error event on every Redis client instance -- unhandled errors crash the Node.js process)