AI Prompt for Caching Strategies

Design caching strategies with this AI prompt: layer selection, key design, invalidation, stampede protection, and cache-aside code patterns.

The prompt

Role: You are a caching architect who designs strategies that are fast AND correct.

Context: System: [SYSTEM]. Read/write ratio: [READ_WRITE]. Data change frequency: [CHANGE_FREQ]. Staleness tolerance: [STALENESS]. Scale: [SCALE].

Task: 1) Design the caching layers: what to cache where (CDN, application cache, DB query cache) with justification per layer. 2) Design cache keys and TTLs driven by [CHANGE_FREQ] and [STALENESS]. 3) Solve invalidation: the strategy for each cached item (TTL, write-through, write-behind, event invalidation) — invalidation is the hard part, be specific. 4) Protect against stampedes (thundering herd) on cache miss and cold start. 5) Provide the cache-aside code pattern for the hottest path. 6) Define hit-rate targets and what to do when they drop.

Format: Layer design first, then keys/TTLs, then the invalidation plan (the centerpiece), then stampede protection, then code, then targets.

Constraints: Every cached item needs an invalidation story — "TTL handles it" is only acceptable within [STALENESS]. Design for the cold-start case explicitly. Never cache without a measured hit-rate target.

Variables to fill in

Replace each [variable] in the prompt with your own details:

[SYSTEM] [READ_WRITE] [CHANGE_FREQ] [STALENESS] [SCALE]

Example input

SYSTEM=product catalog API, READ_WRITE=95% reads, DATA=product details change 2x/day, STALENESS=5 min acceptable, SCALE=50k req/min

How to use this prompt

State the read/write ratio and staleness tolerance — they drive every caching decision. Name what changes rarely; that is your cache's best friend.

Tips for the best results

Write the invalidation plan first; it is where caching strategies fail.
Ask for the stampede protection — flash traffic on an empty cache is a classic outage.
Monitor hit rates from day one; a cache nobody measures is a liability.

Frequently asked questions

What do I need to specify?

It designs the full strategy (layers, keys, invalidation, stampede protection) from your read/write ratio and staleness tolerance — the two key inputs.