No matter how you like to participate in developer communities, Pulumi wants to meet you there. If you want to meet other Pulumi users to share use-cases and best practices, contribute code or documentation, see us at an event, or just tell a story about something cool you did with Pulumi, you are part of our community.

Pulumi Community

I think stack references will help you here:
<https://www.pulumi.com/docs/intro/concepts/stack/#stackreferences>

sorry <@UCWG26BH7> my bad for not being more clear -- yes, I'm using a stack reference but I can't see how can I say "Hey, give me the app gateway ID reference from the core stack, and now use that to create another backend pool"