Is there a way to ensure that a stack is using the correct backend? Having to remember to log in and out all the time is very error prone.

You can set the backend as a project-level setting with the backend.url key in

Pulumi.yaml

or as an operation-level setting with the

PULUMI_BACKEND_URL

env var.

Cool thanks

We are also likely to start storing the backend info in the stack file in the future to address this scenario even more directly. https://github.com/pulumi/pulumi/issues/2996 is an issue tracking this.