docker-compose wordpress with rerun-able volumes

There are several tutorials and files for running wordpress in docker. For me nearly none of them worked, therefore i wrote my own rerunable docker-compose file, which I like to share here now:

wordpress:
  image: wordpress
  container_name: wordpress
  links:
   - mysql
  ports:
   - "80:80"
  environment:
    WORDPRESS_DB_USER: root
    WORDPRESS_DB_NAME: wordpress
    WORDPRESS_DB_PASSWORD: "ch4ngeThis!"
  volumes:
    - /var/www/html/
mysql:
  image: library/mysql:latest
  mem_limit: 256m
  container_name: wordpress-mysql
  environment:
    - MYSQL_ROOT_PASSWORD=ch4ngeThis!
    - MYSQL_DATABASE=wordpress
    - MYSQL_USER=wordpress
    - MYSQL_PASSWORD=ch4ngeThis!
  volumes:
    - /var/lib/mysql

Just put this code into docker-compose.yml, change the passwords accordingly and run a new wordpress simply by:

docker-compose up