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Comment by edfletcher_t137 | Hacker News Reader

The article is titled "for dev and prod" (emphasis on the latter), yet the very first suggestion is to bind-mount your source outside the container so you can mess with it at any time? How is this good advice for production?! (Update: this is indeed great advice for development, and it's actually in a sub-section dedicated to that! My bad.)

Update: reading comprehension, it's a thing! :) Thanks chrsig for pointing out that this is under an appropriate sub-heading. D'oh!

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Just curious, why would a bind-mount be bad in production? I understand if you're running multiple app servers and need the code to be deployed in a lot of places that they'd be bad, but if you're just using a single server, what's the downside of using bind-mounts? You could use git to push code changes up to your server, and they'd be picked up immediately without having to rebuild and push an image.

Usually for production you want to know with 100% certainty what version of the software is running. Whilst you can do that with Git commit hashes you can't be sure no one has performed a hotfix and modified code on the production server which is not committed to source control. Then there's also the potential problem of pulling the latest updates from source control but forgetting to restart the container so it's not obvious you're actually running outdated code.

It's also a lot easier if there's a bad deploy to roll back the update by reverting the image tag in the compose file and restarting rather than checking out specific older commits and risk getting into a funky state with detached heads and the like.

This, 100%. Reproducibility, traceability and auditability all go out the window when you allow source modification on in production directly. You never want to ask "what's running in production" only to be greeted by crickets in response, or worse a lone "my branch from five days ago."

it's under a subheading of

> Docker Compose Best Practices for Development

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