Build a Transactional Email System
Set up a complete email system with templates, sequences, and delivery tracking. Use Resend and React Email for beautiful transactional emails.
Email architecture: Resend + React Email
Resend is the modern alternative to SendGrid and Mailgun. It has a generous free tier (100 emails/day) and a developer-friendly API. React Email lets you build email templates as React components — type-safe, reusable, and previewable in the browser. Ask Claude Code: "Create a Next.js project for an email system. Install Resend and React Email. Set up a preview server for email templates. Create the project structure with templates in emails/ and API routes for sending in app/api/email/."
Building beautiful email templates
Ask Claude Code: "Create five email templates using React Email components: welcome email (for new signups), password reset, order confirmation, weekly digest, and a promotional announcement. Each template should be responsive, work in Outlook and Gmail, and use a consistent brand header/footer. Use Tailwind-style utility classes from React Email's components." Preview each template at localhost:3000/preview to see how they render in email clients.
Building the sending API
Ask Claude Code: "Create API routes for sending each email type. POST /api/email/welcome accepts a name and email. POST /api/email/digest accepts a user ID and generates the digest content. Each route should validate inputs with Zod, send via Resend, and log the result. Add a generic POST /api/email/send route that accepts a template name and data for flexibility." This gives you a reusable email API that any part of your application can call.
Drip sequences and scheduled sends
Ask Claude Code: "Create a drip email sequence system. When a user signs up, they should receive: welcome email immediately, getting started guide at day 1, tips email at day 3, feedback request at day 7, and an upgrade prompt at day 14. Use a database table to track which emails each user has received and a cron endpoint that checks for pending sends." This is the foundation of an email marketing system that would cost hundreds per month from a SaaS provider.
Email Automation
This guide is hands-on and practical. The full curriculum covers the conceptual foundations in depth with structured lessons and quizzes.
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