[IanCal]

You just build it. I'm not sure I understand the issue.

If you really want then just tag them, but building with a cache would be very quick when you swap.

[ParetoOptimal]

I'm pretty sure everyone prefers "check out branch, run build command" to transparently do the right thing rather than mental book-keeping of "does the state of my docker container match the Dockerfile of my feature branch"?

[IanCal]

Yes, that would be "docker build". Or docker compose if you want to do more things and organise the volume mapping side/other dependencies.

> does the state of my docker container match the Dockerfile of my feature branch"

Why track the state of your docker container? Just build it.