Skills

Chapter 4 of 28

Encore Cache

Cache data in Redis from Encore.ts using CacheCluster and typed keyspaces from encore.dev/storage/cache.

1 minute · 115 words · 9 sections

Encore Caching (Redis)

Instructions

Encore’s cache is a typed wrapper around Redis. Declare a CacheCluster once, then create Keyspace objects for each shape of data you need.

Cluster

import { CacheCluster } from "encore.dev/storage/cache";

const cluster = new CacheCluster("my-cache", {
  evictionPolicy: "allkeys-lru",
});

Reference a cluster from another service: const cluster = CacheCluster.named("my-cache");

Eviction policies: "allkeys-lru" (default), "noeviction", "allkeys-lfu", "allkeys-random", "volatile-lru", "volatile-lfu", "volatile-ttl", "volatile-random".

Keyspace types

Each keyspace has a key shape (used to build the Redis key from keyPattern) and a value type.

import {
  StringKeyspace,
  IntKeyspace,
  FloatKeyspace,
  StructKeyspace,
  StringListKeyspace,
  NumberListKeyspace,
  StringSetKeyspace,
  NumberSetKeyspace,
  expireIn,
} from "encore.dev/storage/cache";

// Strings
const tokens = new StringKeyspace<{ tokenId: string }>(cluster, {
  keyPattern: "token/:tokenId",
  defaultExpiry: expireIn(3600 * 1000),
});
await tokens.set({ tokenId: "abc" }, "value");
const val = await tokens.get({ tokenId: "abc" }); // undefined on miss

// Integers (atomic counters)
const counters = new IntKeyspace<{ userId: string }>(cluster, {
  keyPattern: "requests/:userId",
  defaultExpiry: expireIn(10 * 1000),
});
const count = await counters.increment({ userId: "user123" }, 1);

// Structs (JSON)
interface UserProfile { name: string; email: string; }
const profiles = new StructKeyspace<{ userId: string }, UserProfile>(cluster, {
  keyPattern: "profile/:userId",
  defaultExpiry: expireIn(3600 * 1000),
});
await profiles.set({ userId: "123" }, { name: "Alice", email: "alice@example.com" });

// Lists
const recent = new StringListKeyspace<{ userId: string }>(cluster, {
  keyPattern: "recent/:userId",
});
await recent.pushRight({ userId: "user123" }, "item1", "item2");

// Sets
const tags = new StringSetKeyspace<{ articleId: string }>(cluster, {
  keyPattern: "tags/:articleId",
});
await tags.add({ articleId: "post1" }, "typescript", "encore");
const has = await tags.contains({ articleId: "post1" }, "typescript");

Multi-field key patterns

interface Key { userId: string; resourcePath: string; }

const requests = new IntKeyspace<Key>(cluster, {
  keyPattern: "requests/:userId/:resourcePath",
  defaultExpiry: expireIn(10 * 1000),
});

Expiry helpers

import {
  expireIn,          // milliseconds
  expireInSeconds,
  expireInMinutes,
  expireInHours,
  expireDailyAt,     // a specific UTC time each day
  neverExpire,
  keepTTL,           // keep existing TTL when updating
} from "encore.dev/storage/cache";

Write options

await keyspace.set(key, value, { expiry: expireInMinutes(30) });
await keyspace.set(key, value, { expiry: keepTTL });
await keyspace.setIfNotExists(key, value);  // throws CacheKeyExists if present
await keyspace.replace(key, value);          // throws CacheMiss if absent

Errors

import { CacheMiss, CacheKeyExists } from "encore.dev/storage/cache";

const value = await keyspace.get(key);  // undefined on miss (does not throw)

Guidelines

Declare CacheCluster and keyspaces at package level.
Pick the most specific keyspace type — IntKeyspace for counters gives you atomic increment/decrement for free.
get() returns undefined on miss; replace() and setIfNotExists() throw on conflict.
Local development uses an in-memory Redis with a ~100-key cap — don’t load-test it.
For durable storage, use encore-database (Postgres) or encore-bucket (object storage) instead.

Install this repository

$ npx skills add encoredev/skills

» /plugin marketplace add encoredev/skills

Skills install per repository, not per chapter — the CLI has no documented per-skill form, so we do not print one.

About this skill

Trigger

Cache data in Redis from Encore.ts using `CacheCluster` and typed keyspaces from `encore.dev/storage/cache`. Type-safe key/value access with TTLs, atomic increments, and per-keyspace data shapes.

The verbatim description from this skill’s front matter — the string an agent matches on to decide whether to load it.

Colophon for this issue

Colophon

How this issue was made

Source

github.com/encoredev/skills, branch main, last pushed 15 May 2026.

Licence

Apache-2.0 — the text of every chapter is reproduced unmodified, frontmatter included, under the upstream licence.

Discovery

28 chapters found by walking the repository tree for SKILL.md, not by matching a directory convention. One layout observed: encore/*/SKILL.md.

Issue colours

Resolved from a deterministic hash of the owner name. Two accent tones are generated per issue and each is proven against its own ground before it ships: a single accent that passes AA on both light and dark paper is arithmetically impossible.

Heading repairs

1 repair applied to this chapter so the document has one h1 and no skipped levels:

Shifted “9 headings” from h1 to h2 so the chapter title is the only h1.

Spec compliance

28 editorial notes across 28 of 28 chapters. They are printed in the margin of each chapter rather than as errors here.

Encore API — 1 note
Encore Auth — 1 note
Encore Bucket — 1 note
Encore Cache — 1 note
Encore Code Review — 1 note
Encore Cron — 1 note
Encore Database — 1 note
Encore Frontend — 1 note
Encore Getting Started — 1 note
Encore Go API — 1 note

and 18 more.

Images

Images inside a chapter come from the upstream repository. Where the author gave no alternative text we mark the image decorative rather than inventing a description — a plausible caption we made up is worse than none for the reader who depends on it.

Marketplace

A plugin manifest is published at .claude-plugin/marketplace.json by Encore, declaring 1 plugin. It is read for editorial metadata only — never as the skill index, which is always the repository tree.

Signal

Install counts come from skills.sh. They measure downloads, not quality, and an unranked repository is not an unread one.

Agent surfaces

The whole issue is available as one markdown document at /encoredev/skills.md, and each chapter at its own .md URL.

Publication

Set by Skills Docs from the source repository. Body text is Literata at the reader’s chosen size and measure; code is Geist Mono. Nothing on this page was written by us except this paragraph.

Encore Caching (Redis)

Encore’s cache is a typed wrapper around Redis. Declare a CacheCluster once, then create Keyspace objects for each shape of data you need.

import { CacheCluster } from "encore.dev/storage/cache";

const cluster = new CacheCluster("my-cache", {
  evictionPolicy: "allkeys-lru",
});

Reference a cluster from another service: const cluster = CacheCluster.named("my-cache");

Eviction policies: "allkeys-lru" (default), "noeviction", "allkeys-lfu", "allkeys-random", "volatile-lru", "volatile-lfu", "volatile-ttl", "volatile-random".

Each keyspace has a key shape (used to build the Redis key from keyPattern) and a value type.

import {
  StringKeyspace,
  IntKeyspace,
  FloatKeyspace,
  StructKeyspace,
  StringListKeyspace,
  NumberListKeyspace,
  StringSetKeyspace,
  NumberSetKeyspace,
  expireIn,
} from "encore.dev/storage/cache";

// Strings
const tokens = new StringKeyspace<{ tokenId: string }>(cluster, {
  keyPattern: "token/:tokenId",
  defaultExpiry: expireIn(3600 * 1000),
});
await tokens.set({ tokenId: "abc" }, "value");
const val = await tokens.get({ tokenId: "abc" }); // undefined on miss

// Integers (atomic counters)
const counters = new IntKeyspace<{ userId: string }>(cluster, {
  keyPattern: "requests/:userId",
  defaultExpiry: expireIn(10 * 1000),
});
const count = await counters.increment({ userId: "user123" }, 1);

// Structs (JSON)
interface UserProfile { name: string; email: string; }
const profiles = new StructKeyspace<{ userId: string }, UserProfile>(cluster, {
  keyPattern: "profile/:userId",
  defaultExpiry: expireIn(3600 * 1000),
});
await profiles.set({ userId: "123" }, { name: "Alice", email: "alice@example.com" });

// Lists
const recent = new StringListKeyspace<{ userId: string }>(cluster, {
  keyPattern: "recent/:userId",
});
await recent.pushRight({ userId: "user123" }, "item1", "item2");

// Sets
const tags = new StringSetKeyspace<{ articleId: string }>(cluster, {
  keyPattern: "tags/:articleId",
});
await tags.add({ articleId: "post1" }, "typescript", "encore");
const has = await tags.contains({ articleId: "post1" }, "typescript");

interface Key { userId: string; resourcePath: string; }

const requests = new IntKeyspace<Key>(cluster, {
  keyPattern: "requests/:userId/:resourcePath",
  defaultExpiry: expireIn(10 * 1000),
});

import {
  expireIn,          // milliseconds
  expireInSeconds,
  expireInMinutes,
  expireInHours,
  expireDailyAt,     // a specific UTC time each day
  neverExpire,
  keepTTL,           // keep existing TTL when updating
} from "encore.dev/storage/cache";

await keyspace.set(key, value, { expiry: expireInMinutes(30) });
await keyspace.set(key, value, { expiry: keepTTL });
await keyspace.setIfNotExists(key, value);  // throws CacheKeyExists if present
await keyspace.replace(key, value);          // throws CacheMiss if absent

import { CacheMiss, CacheKeyExists } from "encore.dev/storage/cache";

const value = await keyspace.get(key);  // undefined on miss (does not throw)

Declare CacheCluster and keyspaces at package level.

Pick the most specific keyspace type — IntKeyspace for counters gives you atomic increment/decrement for free.

get() returns undefined on miss; replace() and setIfNotExists() throw on conflict.

Local development uses an in-memory Redis with a ~100-key cap — don’t load-test it.

For durable storage, use encore-database (Postgres) or encore-bucket (object storage) instead.