vercel-kv

Last Updated : 2026-01-21 Version : @vercel/kv@3.0.0 (Redis-compatible, powered by Upstash) Basic Usage : CRITICAL : Always use namespaced keys ( user:123 not 123 ) and set TTL for temporary data. Caching (cache-aside): Rate Limiting : Session Management : Pipeline (batch operations): Key Naming : Use namespaces like user:123 , post:abc:views , ratelimit:ip:endpoint Always : Never : This skill prevents 15 documented issues : Error : Error: KV_REST_API_URL is not defined or KV_REST_API_TOKEN is not defined Source : | GitHub Issue #759 Why It Happens : Environment variables not set locally or in deployment. In monorepos (Turborepo/pnpm workspaces), abstracting @vercel/kv into a shared package can cause Vercel builds to fail even though local builds work. Prevention : Run vercel env pull .env.local and ensure .env.local is in .gitignore . For monorepos, either (1) create client in consuming app not shared package, (2) use Vercel Environment Variables UI to set at project level, or (3) add env vars to turbo.json pipeline config: { "pipeline": { "build": { "env": ["KV_REST_API_URL", "KV_REST_API_TOKEN"] } } } . Error : TypeError: Do not know how to serialize a BigInt or circular reference errors. Also, hset() coerces numeric strings to numbers. Source : | GitHub Issue #727 Why It Happens : Trying to store non-JSON-serializable data (functions, BigInt, circular refs).