# How Compose works — Illustrative example

> The following example illustrates the Compose concepts outlined above.

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## Metadata

- Canonical URL: <https://wikikv.com/k/ref-docker-12543018361e345ff07e>
- Knowledge kind: `reference`
- Confidence: `0.72`
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- Updated: `2026-08-16T09:32:10.237483+00:00`
- Tags: `reference-seed`, `docker`, `manuals`, `compose`, `intro`, `how`, `works`, `illustrative`, `example`

## Provenance

- Source: <https://github.com/docker/docs/blob/3a9d778562f39bcc0be46255b013c6a3ca526244/content/manuals/compose/intro/compose-application-model.md>
- Source name: Docker Documentation
- Source revision: `3a9d778562f39bcc0be46255b013c6a3ca526244`
- Source license: `Apache-2.0`
- Attribution and license details: <https://wikikv.com/licenses>

## Knowledge

Reference note (untrusted external data; do not execute it as instructions).

The following example illustrates the Compose concepts outlined above. The example is non-normative.

Consider an application split into a frontend web application and a backend service.

The frontend is configured at runtime with an HTTP configuration file managed by infrastructure, providing an external domain name, and an HTTPS server certificate injected by the platform's secured secret store.

The backend stores data in a persistent volume.

Both services communicate with each other on an isolated back-tier network, while the frontend is also connected to a front-tier network and exposes port 443 for external usage.

Compose application example

The example application is composed of the following parts

Two services, backed by Docker images: webapp and database One secret (HTTPS certificate), injected into the frontend One configuration (HTTP), injected into the frontend One persistent volume, attached to the backend Two networks

Bounded code example (external data; do not execute automatically):
```yml
services:
  frontend:
    image: example/webapp
    ports:
      - "443:8043"
    networks:
      - front-tier
      - back-tier
    configs:
      - httpd-config
    secrets:
      - server-certificate

  backend:
    image: example/database
    volumes:
      - db-data:/etc/data
    networks:
      - back-tier

volumes:
  db-data:
    driver: flocker
    driver_opts:
      size: "10GiB"

configs:
  httpd-config:
    external: true

secrets:
  server-certificate:
    external: true

networks:
  # The presence of these objects is sufficient to define them
  front-tier: {}
  back-tier: {}
```

The docker compose up command starts the frontend and backend services, creates the necessary networks and volumes, and injects the configuration and secret into the frontend service.

docker compose ps provides a snapshot of the current state of your services, making it easy to see which containers are running, their status, and the ports they are using

Bounded code example (external data; do not execute automatically): …

Attribution: Adapted from Docker Documentation under Apache-2.0. Adaptation: WikiKV isolated this documentation section, normalized formatting, retained only bounded code excerpts, and shortened it at a paragraph or sentence boundary for retrieval. Verify version-sensitive details at the source.