Brad Slavin
Brad Slavin

About Brad

Manager at DuoCircle · Published Author

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Brad Slavin is a manager at DuoCircle, an email security company, and a published author — co-author, with Jim Dunn and John Schumann, of the SalesCoach books Common Sense Selling for Commercial Bankers and Sales Mastery. He writes here about business, technology, sales, and building companies.

I started writing at bradslavin.com years ago as a place to think out loud about the ideas that shaped how I build and work — startups, sales, the technology I was working on, and whatever else had my attention. This is the archive of that writing, brought forward to a faster, simpler home.

Published author

I'm a published author — co-author, with Jim Dunn and John Schumann, of the SalesCoach books below, built on the Common Sense Selling methodology taught at SalesCoach.com. You can find my titles on my Amazon author page.

Background

Before DuoCircle, I was behind NetStumbler.com, one of the original communities for Wi-Fi discovery and wireless networking.

At DuoCircle, much of my work has been acquiring and integrating email products. We acquired Dyn's legacy business — well before Oracle's later acquisition of Dyn — taking on that legacy line so Dyn could focus upmarket and grow its average revenue per user (ARPU). We've since brought Maysoft's SpamSentinel and Verisend products into the DuoCircle family too.

Now

These days I focus on email security and deliverability at DuoCircle, and I'm writing again — short, practical notes on building software businesses, working smarter instead of longer, and the tools I actually use. If that's your world too, let's connect on LinkedIn.

What I write about

  • Email Security
  • Email Deliverability
  • Entrepreneurship
  • SaaS
  • Sales Training

What we build at DuoCircle

I work on email security and deliverability at DuoCircle. Here are the products my team builds — tools that keep email authenticated, deliverable, and safe:

  • DuoCircle — The email security company behind these products — spam filtering, email forwarding, outbound SMTP, and hosted email protection for small businesses.
  • DMARC Report — DMARC monitoring and reporting — analyze aggregate and forensic reports and move your domains toward enforcement (p=reject).
  • AutoSPF — Automatic SPF flattening that keeps your SPF record under the 10 DNS-lookup limit and prevents PermError.
  • Phish Protection — Cloud email security against phishing, spoofing, and business email compromise (BEC) for Microsoft 365 and Google Workspace.
  • NuReply — AI cold-email personalization and inbox warm-up tools that build sender reputation and land emails in the inbox.
  • InboxIssue — Email deliverability testing for corporate inboxes — test against Google Workspace, Office 365, and enterprise security filters.
  • Mailflow Monitoring — Round-trip SMTP and IMAP monitoring that alerts you the moment your email stops flowing.
  • unsent.dev — Developer email delivery platform — REST API, SMTP relay, and SDKs for transactional and marketing email at scale.

Elsewhere

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