Updating where to pull requirements from (not pypi)

[syynni]

Hello,
Is it possible to configure MWAA and aws-mwaa-local-runner to use a different package repo than pypi?

We need to use our own CA repository, and have tried out this example: https://docs.aws.amazon.com/mwaa/latest/userguide/samples-code-artifact.html w/ PIP_INDEX_URL and PIP_EXTRA_INDEX_URL

But modifying our startup.sh with these doesn't seem to have the expected effect -
The environment variables don't appear to be configured in the docker container that is started up (env shows several environment variables, but not PIP_EXTRA_INDEX_URL or PIP_INDEX_URL) but directly updating these env variables in the docker container itself and then running any pip commands does seem to pull from the expected CA repo.

Any information on the best approach for this would be much appreciated.

Alternatively, if anyone just knows how to get env variables properly set in the containers where Airflow will be installing the dependencies, that's mostly what I need to know!

Thanks!