I want to port an existing project  to serverless architecture, but I am having sleepless nights trying to figure out how to do it.
For example I want the UX to be, admin signs up and chooses a domain: "foobar"
a subdomain like "foobar.example.com" is created
the "foobar" domain in itself has it's own user pool. And basically uses a bunch of lambda functions & JS code with docclient to set and retrieve things in DynamoDB tables.
Hopefully you have the idea. But how do I implemented this in my AWS account that each new domain is isolated? A new AWS account everytime, which sounds impractical. Or am I missing some technique?