Memory, Redis, disk, and Memcached share one read-through interface with automatic backfill.

Concurrent callers collapse into one fetch locally, with Redis leases for distributed coordination.

Expire by tag, prefix, pattern, or namespace without throwing away stale fallback state.

Circuit breakers, timeout controls, Prometheus metrics, OpenTelemetry spans, and CLI inspection.

Middleware and helpers for Express, Fastify, Hono, tRPC, GraphQL, and OpenTelemetry.

Try Layercache examples in an isolated worker sandbox directly in the documentation site.