Effect Cache Penetration Shield
The shield for keys that do not exist, which a plain cache cannot protect. A cache only helps for keys that are present, so an attacker iterating random ids misses every time and points the full request rate at the database (the cache-miss attack). A bloom filter seeded with every existing key answers definitely-absent in memory so made-up keys die before the database hears them, and a TTL'd negative cache absorbs repeats for keys that existed then vanished. Index math uses (h >>> 0) so a negative typed-array index can never drop a bloom bit into a false negative. The demo: 50 fake-key requests, 0 database hits. Pinned to effect 4.0.0-beta.98.
npx shadcn@latest add https://ui.aryank.space/r/effect-cache-penetration-shield.jsonInstalls from ui.aryank.space. To add it by hand, copy the files in Files below, or register the @compronents namespace via the docs.
A cache only helps keys that exist. 50 requests for a made-up id all miss, the database confirms nothing, and nothing is cached: every request repeats the full trip.