Your best options are: a. environment varaibles (if that's an option) b. mount the file when you launch the container I'm using (b) for our nginx configs,

Your best options are: a. environment varaibles (if that's an option) b. mount the file when you launch the container I'm using (b) for our nginx configs, you mount only the single config file as read-only, then let chef copy up the config before mounting/launching.