> How do you debug (in dev or prod)

VSCode lets you debug inside a Docker container.

> or in production, do things such as inspecting log files

Logs should be sent out of the container, either directly (mount a /logs folder, push them to Sentry / ELK / etc.) or by simply logging to stdout and having Docker send the logs where you want.

> monitoring system resources

Docker processes are still processes. They show up in `top` and friends just fine.

> running necessary commands if there is something urgent...?

`Docker exec my_container <insert command here>`.

Although I've never even considered doing that. For the past few years the resolution to a production bug has always been "rollback to the previous image, then if any data got borked fix it in the database".