12.1.2.4 Dev Cache Service

A dev cache service runs a containerized caching instance — typically Redis or Memcached — for local development, generally requiring minimal configuration since most caching software needs little setup beyond simply running, and its data is usually acceptable to lose between restarts.

A Minimal Dev Cache Configuration

A development cache service is often one of the simplest entries in a development Compose stack.

services:
  cache:
    image: redis:7
    ports:
      - "6379:6379"

Why This Minimal Configuration Is Usually Sufficient

Since cached data is, by its nature, derived and regenerable, a development cache typically doesn't need persistent storage, seed data, or extensive configuration — the application simply repopulates the cache as it runs.

docker compose restart cache

Restarting this service provides an effectively clean cache state, with the application naturally repopulating it as needed during subsequent use.

Connecting the Application to the Development Cache

The application connects to this cache service exactly as it would to any production cache, just configured to reach this specific, locally running instance.

services:
  backend:
    environment:
      - CACHE_URL=redis://cache:6379

Exposing the Cache Port for Direct Local Inspection

Exposing the cache's port directly allows a developer to connect with their own client tool to inspect cache contents during development, a convenience not typically appropriate for a production cache.

redis-cli -h localhost -p 6379

Why a Dev Cache Service Configuration Matters

A minimal, convenience-oriented development cache configuration provides everything needed for an application to develop and test its caching behavior locally, without requiring the more involved configuration a production cache deployment might warrant.