Docker - Spree — ContextQMD

Building Your Project's Image

Every create-spree-app project builds into a single production image: the web server and background jobs run in one container, and the only dependency is a PostgreSQL database (the single-node topology).

If you haven't ejected yet, do that first:

bash

spree eject

This generates the app source — including its production Dockerfile — in backend/. Make your customizations, then build:

bash

spree build --production                                  # → <project>-spree:latest
spree build --production --tag registry.example.com/my-store:v42

Or with plain Docker, from the project root:

bash

docker build . -f backend/Dockerfile -t my-store

Both produce the same image — and it's exactly what Render and Railway build from your repository. Migrations run automatically on boot.

Running the Image

One app container plus Postgres is a complete deployment:

yaml

services:
  postgres:
    image: postgres:18-alpine
    environment:
      POSTGRES_HOST_AUTH_METHOD: trust
    volumes:
      - postgres_data:/var/lib/postgresql/data
    healthcheck:
      test: pg_isready -U postgres
      interval: 5s
      timeout: 5s
      retries: 5

  web:
    image: my-store   # or ghcr.io/spree/spree:latest for the stock image
    depends_on:
      postgres:
        condition: service_healthy
    environment:
      DATABASE_URL: postgres://postgres@postgres:5432/spree_production
      SECRET_KEY_BASE: change-me-to-a-real-secret
      RAILS_FORCE_SSL: "false"
      RAILS_ASSUME_SSL: "false"
      # Public host used in generated URLs (images/attachments in API
      # responses, email links) — set to your domain or IP in production.
      RAILS_HOST: localhost:3000
    ports:
      - "3000:3000"
    healthcheck:
      test: curl -f http://localhost:3000/up || exit 1
      interval: 10s
      timeout: 5s
      retries: 10
      start_period: 30s

volumes:
  postgres_data:

Start everything:

bash

docker compose up -d

The database is created and migrated on first boot. The app is available at http://localhost:3000.

Scaling out the worker

Background jobs run inside the web container by default. When job load deserves its own process, split it out — same image, no rebuild: set SOLID_QUEUE_IN_PUMA: "false" on web and add a worker service:

yaml

  worker:
    image: my-store
    depends_on:
      postgres:
        condition: service_healthy
    environment:
      DATABASE_URL: postgres://postgres@postgres:5432/spree_production
      SECRET_KEY_BASE: change-me-to-a-real-secret
      RAILS_HOST: localhost:3000
    command: bin/jobs

Required Environment Variables

Variable	Description	Example
`DATABASE_URL`	PostgreSQL connection URL	`postgres://user:pass@host:5432/spree`
`SECRET_KEY_BASE`	Secret key for session encryption	Generate with `bin/rails secret`
`RAILS_HOST`	Public host used in generated URLs — image/attachment URLs in API responses, email links	`store.example.com`
`SOLID_QUEUE_IN_PUMA`	Run background jobs inside the web container (default `true`); set `false` when running a dedicated worker	`true`

See Environment Variables for the full list.

Official Docker Image

To run Spree without any customizations, pull the prebuilt multi-arch image (linux/amd64 and linux/arm64) published to the GitHub Container Registry on every release:

bash

docker pull ghcr.io/spree/spree:latest

Tag	Description
`latest`	Latest stable release
`5.4.0`	Specific version
`5.4`	Latest patch for a minor version

Browse all tags on the GitHub Packages page. The image drops into the compose file above in place of your custom tag.