Docker and CI/CD · Middle · Question 18 of 75

In Compose, what is the difference between the `.env` file and `env_file:`?

1They're identical, and Compose simply merges both of them
2.env is for production values, while env_file is for development
✓Correct answer: .env fills ${VAR} in the YAML; env_file sets container variables

Explanation

The project .env is used for interpolation in compose.yaml. Variables reach the container only through environment: or env_file:.

Further reading

Docker Docs: Compose file reference ↗

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