Docker plone-backend and addon development

I'm looking at the documentation plone/plone-backend – Install Plone 6 – Containers – Official Images — Plone Documentation v6.0-dev
But I'm not seeing how to do add-on development with the plone-backend docker images

This is the command I'm using

docker run -p 8090:8080  -e PLONE_DEVELOP="src/my.content" -e ADDONS="my.content" -e SITE="Plone" -e TYPE="classic" -v $(pwd)/src:/opt/plone/backend/src  plone/plone-backend:6.0.0a4

BTW... it looks like the path in the container changed from previous docker images, which used to hold the src at /plone/instance/src, seems everything is now under /opt/plone/backend

I'm using the volume (-v) to mount the src folder as this is where my custom addon is located.
What I'm seeing is an error.

ERROR: Could not find a version that satisfies the requirement my.content (from versions: none)
ERROR: No matching distribution found for my.content
WARNING: You are using pip version 22.0.4; however, version 22.1.2 is available.
You should consider upgrading via the '/app/bin/python -m pip install --upgrade pip' command.

See this discussion, it may help: Run local acceptence tests with local backend add-on (plone.restapi) - #3 by ksuess

@tiberiuichim …based on the discussion you referenced, I’ll need to map my volume to /app/src

I’ll try that and report the outcome.

It works with /app/src.
This command worked for me:

docker run -p 8090:8080  -e PLONE_DEVELOP="src/my.content" -e ADDONS="my.content" -e SITE="Plone" -e TYPE="classic" -v $(pwd)/src:/app/src  plone/plone-backend:6.0.0a4

The only thing non-standard is that I use port 8090 instead of the more common 8080.

The information is actually available in the Plone 6 docs: