A long-awaited enhancement to API Gateway has finally arrived!
You can now specify a wildcard (*) as the first subdomain of any API Gateway custom domain. This is great new for teams wanting to manage environments via subdomains, or vendors operating multi-tenancy APIs.
There are a handful of caveats (follow the link below), but nothing unexpected. We're definitely going to be making full use of this improvement here at ED HQ!
See how to use wildcard custom domains here: https://docs.aws.amazon.com/apigateway/latest/developerguide/how-to-custom-domains.html#wildcard-custom-domain-names