Email Infrastructure

Production email delivery requires DNS authentication, domain isolation, and provider-agnostic architecture. A single misconfiguration can land your entire domain in spam.

GOOD vs BAD: Domain Strategy

BAD:  Send bulk marketing from example.com
      → Spam complaints tank your main domain reputation
      → Transactional emails (password reset, receipts) start landing in spam
      → Recovery takes weeks of warmup

GOOD: Subdomain isolation with separate reputations
      → mail.example.com        for transactional (password reset, receipts, 2FA)
      → notify.example.com      for product notifications (comments, mentions)
      → marketing.example.com   for bulk campaigns (newsletters, promotions)
      → Each subdomain has independent reputation — one bad campaign does not poison the rest