It's cool that you're doing this!

However, due to an open issue in Docker (moby/moby#2259) we need to chown the volume from the host machine to match user permissions. This is fine but because you did not hardcode the GID also, it changes on each deployment? This means we can't write scripts that do this automatically because the GID value is changing.

See https://github.com/mastodon/mastodon/blob/74903af7ce6a0622752e19b1e0b326ecfa0463cb/Dockerfile#L48-L49 for an approach which sets both.

This allows us to write scripts chown $UID:$GID ... and not have it change in between deployments.