Docker Compose

How Docker Compose works

Many applications need more than one process: a web server, a database, a cache, a background worker. Docker Compose describes them together in a file, usually compose.yaml, with each service's image, environment variables, ports, volumes, and dependencies.

Then:

• docker compose up -d starts everything in the background.
• docker compose logs -f follows output.
• docker compose pull then up -d upgrades.
• docker compose down stops it.

Compose v2 ships as a plugin to the Docker CLI, which is why the command is docker compose with a space.

An example

services:
  app:
    image: example/app:latest
    ports: ["3000:3000"]
    depends_on: [db]
  db:
    image: postgres:16
    volumes: ["db:/var/lib/postgresql/data"]
volumes:
  db:

That file runs an app and its database with a persistent volume.

Why it matters for AI-agent publishing

Self-hosting is only practical if setup is short and upgrades are routine. Compose gives a repeatable setup on any machine with Docker, from a laptop to a small cloud VM.

SocialHandoff supports Docker Compose for self-hosting, alongside an all-in-one image and a ./run.sh script for local use. Set encryption and other settings through environment variables with the SOCIALHANDOFF_ prefix. The self-hosting guide walks through it, and getting started covers first sign-in.