This acts like a DNS (Domain Name System) Resolver, to redirect your domain name to the relevant IP address, other free open source software can be used like PowerDNS.
Assume that you have already got a domain under Route 53 → Sidebar Domains → Registered domains,
define subdomain: {???}.happy.com
Record type: A
Value/Route traffic to: Alias to S3 Website endpoint
Region: {where your bucket}
Bucket: {bucket name}
Evaluate target health: No (if nothing behind the host)