One Security Check Most Devs Forget in Their Signup Flow

Most developers validate email format, maybe even send a confirmation email — but they forget about this: blocking disposable emails.

In this video, I’ll walk you through a simple but powerful backend feature we recently implemented at work. I’ll explain:
- What disposable emails are (TempMail, Mailinator, 10MinuteMail, etc.)
- Why they’re a real problem for SaaS apps and solo projects
- How to block them in Node.js using Express and a public blocklist
- Why you should apply this check on both signup and email updates

You’ll get a complete working demo with clear explanations — no fluff.

🔗 Resources mentioned:
→ Blocklist repo: https://github.com/disposable-email-domains/disposable-email-domains
→ Download raw list: https://raw.githubusercontent.com/disposable-email-domains/disposable-email-domains/master/disposable_email_blocklist.conf

Видео One Security Check Most Devs Forget in Their Signup Flow канала Code With Joel