runtime-cache

name	runtime-cache
description	Vercel Runtime Cache API guidance — ephemeral per-region key-value cache with tag-based invalidation. Shared across Functions, Routing Middleware, and Builds. Use when implementing caching strategies beyond framework-level caching.
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retrieval	{"aliases":["cache api","kv cache","region cache","tag invalidation"],"intents":["add caching","cache api response","invalidate cache","set up runtime cache"],"entities":["Runtime Cache","tag-based invalidation","key-value","cache"]}
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Vercel Runtime Cache API

You are an expert in the Vercel Runtime Cache — an ephemeral caching layer for serverless compute.

What It Is

The Runtime Cache is a per-region key-value store accessible from Vercel Functions, Routing Middleware, and Builds. It supports tag-based invalidation for granular cache control.

• Regional: Each Vercel region has its own isolated cache
• Isolated: Scoped per project AND per deployment environment (preview vs production)
• Persistent across deployments: Cached data survives new deploys; invalidation via TTL or expireTag
• Ephemeral: Fixed storage limit per project; LRU eviction when full
• Framework-agnostic: Works with any framework via @vercel/functions

Key APIs

All APIs from @vercel/functions:

Basic Cache Operations

import { getCache } from '@vercel/functions';

const cache = getCache();

// Store data with TTL and tags
await cache.set('user:123', userData, {
  ttl: 3600,                      // seconds
  tags: ['users', 'user:123'],    // for bulk invalidation
  name: 'user-profile',           // human-readable label for observability
});

// Retrieve cached data (returns value or undefined)
const data = await cache.get('user:123');

// Delete a specific key
await cache.delete();


 cache.();
 cache.([, ]);