Configuration build up question

Hi All,

I follow some users on Github and Matt8707 make use of packages.
(GitHub - matt8707/hass-config: ✨ A different take on designing a Lovelace UI (Dashboard))

Integrations, automations in one yaml file for specific device or area etc.

I want change my whole config to next level :slight_smile:

I’m wondering if a platform sensor for example can be used in multiple yaml files.
I have some automations based on a door sensor. Want create same idea to use packages.
But when you only can use 1 time a sensor integration in 1 yaml file then I have to make some reverence where this sensor is used.

I hope someone can understand me and can tell me little bit more about package use of config.