https://devops.stackexchange.com/questions/537/why-is-one-not-allowed-to-use-a-boolean-in-a-docker-compose-yml
@@ -25,4 +25,4 @@ services:
MYSQL_DATABASE: my_wiki
MYSQL_USER: wikiuser
MYSQL_PASSWORD: example
- MYSQL_RANDOM_ROOT_PASSWORD: yes
+ MYSQL_RANDOM_ROOT_PASSWORD: 'yes'