No module named 'addons' in Rasa-X

I have custom slots that work fine in Rasa (version 2.3.1). I followed the docs on Custom Slot Types (found here: Domain) and made sure that my directory structure matches the one detailed in the docs example.

├── actions
│   ├──
│   └──
├── addons
│   ├──
│   ├── __pycache__
│   │   ├── __init__.cpython-37.pyc
│   │   └── estimate_slot.cpython-37.pyc
│   └──
├── config.yml
├── credentials.yml
├── data
│   ├── lookup.yml
│   ├── nlu.yml
│   ├── rules.yml
│   └── stories.yml
├── domain.yml
├── endpoints.yml
├── poetry.lock
├── pyproject.toml
└── tests
    └── test_stories.yml

Also, my addons are referenced with a module path exactly as the ones suggested in the docs. For example:

type: addons.estimate_slot.Estimate

… where Estimate is my custom Slot class class Estimate(Slot):

However, this is not working on my Rasa-X server. Whenever I push any code with my addon custom slots or try to load a branch using my custom slot types, Rasa-X refuses to update and I get this error in the rasa_x container when it raises an exception:

ModuleNotFoundError: No module named ‘addons’

This prevents the changes appearing on Rasa-X and it thus (obviously) refuses to train a new model.

Please let me know if I missed something or if my structure looks off.

You need to mount the addons folder into the /app directory in your rasa production, rasa worker and rasa x container.