Does anyone one implemented something similar to cfn-signal to make sure ec2 user data was properly executed. I am planning to use ssm param store. User data will have last step where it creates param in ssm with status. One thing is not clear is how to do pulling on pulumi side. I can lock while loop, but wander if there is a better way to do the pooling

Instead of userdata, I think you could potentially put your script in a local or remote command and execute via SSM or SSH instead, but I haven't implemented this pattern yet so I don't know how tricky it is. https://www.pulumi.com/registry/packages/command/api-docs/

Thanks for your reply. Correct me if I am wrong, but I don't think you can wait for execution of the ssm document. The whole Idea is to have exposit response from ec2 that all setup went well and all application up and running.