Zachary Myers

One Time PIN: caller verification that saved over $300K a year

I built One Time PIN (OTP), a tool that let Customer Care verify a caller. In 2023 I led the migration that moved the tool's code delivery onto the Notification Hub.

Summary

Role
Lead Continual Service Improvement Engineer, UScellular, Jan 2021 – Aug 2025. Built a bare-bones version of One Time PIN. Led the OTP Notification Hub 2.0 migration in 2023.
Team
Worked with developers and middleware teams to take One Time PIN to production. In 2023, about 25 people across middleware, development, CRM, security, network engineering and care operations worked on the OTP Notification Hub 2.0 migration under my coordination.
Results
Saved over $300K a year. After the 2023 migration, delivery averaged 0.18 seconds with a 1.02-second maximum. The new Notification Hub instance was reusable by other frontline tools.
Systems
IT-managed Notification Hub · SMSC/MMSC · Email-to-SMS, kept as a fallback

Problem

  • Customer Care needed a traceable way to verify a caller. The customer-facing organization had been about to buy a third-party product for roughly $300K a year.
  • One Time PIN sent its codes through an Email-to-SMS path. Before the 2023 migration, that path had caused four Sev1 outages and slow delivery at peak hours, which pushed up frontline handle time.

What I did

  • I built a bare-bones version of One Time PIN and got it approved. Then I worked with developers and middleware teams to take it to production.
  • A Customer Care associate pressed one button, and a code went to the primary phone on the account. The send was traceable.
  • I led the OTP Notification Hub 2.0 migration. I moved delivery onto the IT-managed Notification Hub, straight to the SMSC/MMSC. Those were the carrier's text and picture messaging centers. Email-to-SMS was kept as a fallback.
  • About 25 people across middleware, development, CRM, security, network engineering and care operations worked on the migration under my coordination.

What changed

  • One Time PIN saved over $300K a year.
  • After the migration, delivery averaged 0.18 seconds with a 1.02-second maximum.
  • The new Notification Hub instance was reusable by other frontline tools.

How delivery worked after the 2023 migration

  1. One-button press by the associate
  2. Notification Hub
  3. SMSC/MMSC
  4. Code to the primary phone on the account

Fallback: Email-to-SMS

After the 2023 migration, a code followed this path. The associate pressed one button. The IT-managed Notification Hub sent the code straight to the SMSC/MMSC. From there it reached the primary phone on the account. Email-to-SMS was kept as a fallback path.

Details are limited to what can be shared publicly.

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