Building plug-n-play serverless million scale reusable OTP service on AWS

Now-a-days due to security considerations passwords alone aren’t enough. One Time Password(OTP) has become norm in logins, critical transactions or new user verification in most consumer apps especially banking, travel and healthcare etc. Third-party OTP services offer a quick solution but they often come with high costs, vendor-lock in rate limits, lack of control and customizations.

In this talk, I’ll share the blueprint and our journey for how we built our own centralized OTP service on AWS, slashing our authentication costs while gaining full control over our user journey. We’ll walk through the serverless architecture that powers millions of OTP deliveries via email and SMS for a fraction of the price of commercial services following modern engineering practices which is maintainable and compliant also. I’ll break down the key design decisions, the trade-offs we made, and how this low-maintenance platform delivers massive business value by being reliable, scalable, and incredibly cheap to run.