One thing to note is that you can have multiple fig.yml files. So, you could set slightly different configuration parameters (perhaps use `environment` etc.) f

One thing to note is that you can have multiple fig.yml files. So, you could set slightly different configuration parameters (perhaps use `environment` etc.) for different places you are using fig using the `-f` option to specify a different fig.yml. I don't think entering a container is bad for development, in fact it's a frequent pattern (to run things like you describe rake etc.). With the release of docker exec this becomes easier too. I think of it kind of like bind-mounting a directory in the container to do code editing without having to rebuild- as long as you are using ADD for every stage afterwards that should be fully automated (QA, test, production) then you are in the clear.