Interpolation

The manifest file accepts interpolation in the same format as Docker Compose files. Any text enclosed in ${} is treated as a variable and replaced at runtime with the value from the current environment.

Example

# export a variable
$ export AGE_KEY_FILE=~/.config/sops/age/keys.txt

docker:
  context: default
  identifier: my_project

sops:
  age:
    key_file: ${AGE_KEY_FILE}

docker:
  context: default
  identifier: my_project

sops:
  age:
    key_file: ~/.config/sops/age/keys.txt

This is especially useful when handling secrets and sensitive values outside of Dockform, such as in GitHub Actions or other CI/CD systems. By interpolating environment variables, you can keep credentials and tokens out of the manifest file while still making them available at runtime.

E.g.:

stacks:
  website:
    root: website
    environment:
      inline:
        - API_KEY=${GITHUB_TOKEN}