Node.js guide explains generating and sending SMS one-time passwords through an API

A DEV Community article explains how to build SMS verification codes in Node.js using locally generated one-time passwords sent through a generic SMS provider API. It recommends treating message delivery as a state transition, storing only a hashed code with an expiry and attempt counter, and making send requests idempotent so retries do not produce ambiguous logins. The author argues that timeouts leave delivery status unknown, so blind retries can send duplicate texts and unnecessary charges. The piece also recommends keeping OTP authentication separate from report generation and emailing, which should run as independent queued jobs with their own retry policies. The accompanying TypeScript example uses a cryptographically secure random generator and a provider-agnostic gateway interface.