redis

name	redis
description	Redis data structures, caching patterns, pub/sub, rate limiting, and session management
layer	domain
category	database
triggers	["redis","caching","rate limiting","pub/sub","session store","redis cache","distributed lock"]
inputs	[{"use_case":"Caching, rate limiting, pub/sub, session management, queues"},{"requirements":"TTL policies, data structures, clustering needs"},{"client":"ioredis | redis (node-redis) | upstash (optional)"}]
outputs	[{"redis_client":"Client configuration and connection setup"},{"cache_patterns":"Caching strategies with invalidation"},{"data_structures":"Appropriate Redis data structure recommendations"},{"rate_limiter":"Rate limiting implementation"}]
linksTo	["caching","nodejs","microservices","message-queues"]
linkedFrom	["caching","authentication","ecommerce"]
preferredNextSkills	["caching","nodejs"]
fallbackSkills	["caching"]
riskLevel	low
memoryReadPolicy	selective
memoryWritePolicy	none
sideEffects	[]

Redis Skill

Purpose

Implement Redis-backed caching, rate limiting, pub/sub messaging, session management, and distributed locks. This skill covers Redis data structures, caching patterns with proper invalidation, and serverless-compatible clients like Upstash. Redis is not just a cache -- it is a versatile data structure server.

Key Concepts

Data Structure Selection

STRING:   Simple key-value. Counters, cache entries, session data.
          SET key "value" EX 3600

HASH:     Object-like fields. User profiles, settings, product details.
          HSET user:123 name "Jane" email "[e-mail]"

LIST:     Ordered collection. Activity feeds, queues, recent items.
          LPUSH feed:user:123 "posted a comment"

SET:      Unique collection. Tags, followers, online users.
          SADD tags:post:456 "react" "nextjs" "typescript"

SORTED SET: Ranked collection. Leaderboards, rate limiting, priority queues.
            ZADD leaderboard 1500 "user:123"

STREAM:   Append-only log. Event sourcing, message queues.
          XADD events * type "order.created" orderId "789"

When to Use Redis vs. Database

USE REDIS:
  - Data that changes frequently and is read often (cache)
  - Temporary data with TTL (sessions, OTP codes, rate limits)
  - Real-time features (pub/sub, presence, typing indicators)
  - Counters and aggregations (view counts, rate limits)
  - Distributed locks (prevent concurrent operations)

USE DATABASE:
  - Source of truth (orders, users, products)
  - Complex queries (joins, aggregations, full-text search)
  - Data that must survive restarts without rebuild
  - Relational data with integrity constraints

Patterns

Client Setup

// lib/redis.ts (ioredis)
import Redis from 'ioredis';

export const redis = new Redis(process.env.REDIS_URL!, {
  maxRetriesPerRequest: 3,
  retryStrategy(times) {
    const delay = Math.min(times * 50, 2000);
    return delay;
  },
  : ,
});


 {  }  ;
  redis =  ({
  : process..!,
  : process..!,
});