💾Thananjhayan
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Docker Compose

July 9, 2025

Compose defines and runs multiple containers together from one YAML file.

Commands

docker compose -f filename up      # start all services
docker compose -f filename down    # stop and remove them
docker compose build               # build all images
docker compose push                # push all images to a registry

docker compose (space, new) vs docker-compose (hyphen, old) — both work; use whichever is installed.

If the file is the default docker-compose.yml in the current folder, you can drop -f filename and just run docker compose up.

Example compose file

version: "3.8"
services:
  backend:
    build:
      context: ./backend
      dockerfile: Dockerfile
    image: <dockerhub-username>/<name>-backend:latest
    ports:
      - "5000:5000"
  frontend:
    build:
      context: ./frontend
      dockerfile: Dockerfile
    image: <dockerhub-username>/<name>-frontend:latest
    ports:
      - "8080:80"
    depends_on:
      - backend
  • context — folder to build from; dockerfile — which Dockerfile to use.
  • image — the tag the built image gets (needed to push to Docker Hub).
  • ports — HOST:CONTAINER (open localhost:8080 in the browser).
  • depends_on — start backend before frontend.

See also [[docker-hub-push-images]] and [[docker-multi-container-app]].

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