What is Docker Compose?
Docker Compose defines and runs related container services using one configuration file.
How it works and where it is used
A web app, database and cache can be separate services, with networks, ports, variables and volumes in the file. This improves repeatability in development and small deployments. Recreating a container can erase temporary contents; durable data needs volumes and backups.
Limits, safety and selection criteria
A Compose file does not automatically solve production secrets, scaling, health checks or resilience across hosts. Pin image versions and avoid exposing unnecessary ports. Test configuration and rollback before deployment. A team can start its app and database from the same Compose file, reducing hand-configured version and port differences. But placing passwords in plaintext or exposing the production database port publicly is dangerous. Startup order is not readiness: the app should wait until the database can actually accept queries. Back up persistent volumes and use trusted images. Keep environment differences understandable and secrets out of source control. Before a real rollout, test what happens when one container restarts or a dependency becomes unavailable.