api-database-upstash

# Upstash Patterns > **Quick Guide:** Upstash provides a **REST/HTTP-based Redis client** (`@upstash/redis`) designed for serverless and edge runtimes where TCP connections are unavailable. Unlike ioredis/node-redis, every command is an HTTP request -- no persistent connections, no connection pools, no teardown. The client **automatically serializes/deserializes JSON** (objects stored via `set` come back as objects from `get`), which is convenient but has gotchas with large numbers and cross-client compatibility. Use `redis.pipeline()` to batch commands into a single HTTP request, `redis.multi()` for atomic transactions, and `@upstash/ratelimit` for pre-built rate limiting algorithms. For background jobs, use `@upstash/qstash` which pushes messages to your API via HTTP webhooks. --- <critical_requirements> ## 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 `Redis.fromEnv()` for initialization in production code -- never hardcode `UPSTASH_REDIS_REST_URL` or `UPSTASH_REDIS_REST_TOKEN` values)** **(You MUST handle the `pending` promise from `@upstash/ratelimit` responses in edge runtimes -- use `context.waitUntil(pending)` on Vercel Edge/Cloudflare Workers or analytics data is lost)** **(You MUST use `redis.pipeline()` when issuing 3+ independent commands in a single handler -- each command is a separate HTTP round-trip without pipeli...