I built my own email verification engine because I was tired of paying $400+/mo for verification tools

Not sure if anyone else here ran into this problem, but when you're running cold email campaigns the verification costs get ridiculous once volume increases.

A lot of the big tools charge per email forever.

So out of curiosity I built my own verification engine and started running my lists through it instead.

After a few months it actually turned into a full system:

• bulk verification API
• dashboard
• provider-specific SMTP verification (Gmail, Outlook, Yahoo etc.)
• disposable detection database
• catch-all scoring + deliverability scoring

Stack is Go + PostgreSQL + Redis running in Docker.

The interesting part is the infrastructure requirement is actually pretty small. It can run on a basic server (even Oracle Cloud free tier).

Which made me realize something:

Most agencies running cold outreach could probably just host their own verification engine instead of paying monthly forever.

So I cleaned up the codebase and made it deployable.

Right now I'm testing offering self-hosted licenses to a few agencies where I help deploy it on their server and they can run unlimited verifications.

If anyone here runs large cold email campaigns I'd be curious:

How much are you paying monthly for verification right now?

Also happy to run a free verification test on a list if anyone wants to compare results with their current tool.

Demo if anyone is curious:
https://verifications.email