How to Add Email Notifications to Your AI-Built App

Welcome emails after signup. Password reset links. Order confirmations. Notification digests. Invoice receipts. Most AI tools don't add email because it requires a third-party service and server-side code. If your app has users, it needs email.

Resend is the simplest — modern API, great developer experience, React Email for templates. SendGrid has a generous free tier (100 emails/day). Postmark is the most reliable for transactional email. AWS SES is cheapest at scale but harder to set up. For most vibe coded apps, Resend is the best starting point.

Transactional emails are triggered by user actions (password reset, order confirmation). Marketing emails are sent to lists (newsletters, promotions). Use different providers for each — transactional email needs high deliverability and fast delivery. Never send marketing email from your transactional domain.

Create an API route or Edge Function that sends email. Use the email provider's SDK. Build email templates with React Email (works with Resend) or simple HTML. Trigger emails from your application logic — after signup, after purchase, after important events. Always send email asynchronously so it doesn't slow down the user's request.

Set up SPF, DKIM, and DMARC DNS records — without these, your emails go to spam. Verify your sending domain. Start with a small volume and gradually increase. Monitor bounce rates and complaint rates. Use a subdomain for email (mail.yourdomain.com) to protect your main domain's reputation.