I’m new to home assistant and was shocked to see that integration with nest is no longer available. I’m currently using an ISY994i and have full integration with the use of the Polyglot 2.0 and this integration https://github.com/Einstein42/udi-nest-poly. There is no need for a developer account and it work great. Hopefully someone much smarter than me can determine what method is available and port over to work with Home Assistant.