I replaced Resend across 12 SaaS projects with my own email service
The author describes migrating 12 SaaS projects from Resend to their own self-built transactional email service called Mailwain, citing better control and lower costs.
Background
- **Resend** is a popular third-party email API service that developers use to send transactional emails (password resets, order confirmations, notifications) from their apps. It's one of several such services (alongside SendGrid, Mailgun, Postmark), pricing usually by email volume.
- **Transactional email** means automated, triggered-by-user-action emails (not marketing newsletters). Reliability and deliverability (not landing in spam) are critical.
- The article's author built a custom email sending system called **Mailwain**. They explain migrating 12 different SaaS (software-as-a-service) projects away from Resend to their own mail infrastructure, likely for cost savings, control, or deliverability improvements.
- This reflects a broader tension in indie/SaaS engineering: pay for a specialized email API vs. self-host or build your own stack (using tools like AWS SES, Postfix, or custom SMTP). The piece likely shares technical lessons and trade-offs from making that switch.