DNS records are all you need. MX for the mail servers, plus hopefully you're setting up SPF/DKIM records to verify authenticity of mails sent from your domain. You can even set up CNAME records to point subdomains to the GMail, Calendar, etc. web GUIs.
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DNS records are all you need. MX for the mail servers, plus hopefully you're setting up SPF/DKIM records to verify authenticity of mails sent from your domain. You can even set up CNAME records to point subdomains to the GMail, Calendar, etc. web GUIs.