Backend Engineer, MTA
Resend is building the most accessible email platform for developers. As we’ve grown to 4M+ users and continue to onboard thousands of new users every day, the pressure of maintaining a safe place for good senders continues to build.
This role is fully remote-based in Americas or European time zones, with some expected travel for team off-sites, conferences, meetups, and more.
Read more about how we work, how we hire, and what we value here.
In this role, you will…
Build and operate Resend’s email transport infrastructure
Work on SMTP delivery, MTA systems, routing, retries, backoff strategies, and delivery controls
Design systems for domain-level, provider-level, customer-level, and IP-level throttling
Build infrastructure for shared IP pools, dedicated IPs, warmup execution, and reputation-aware routing
Improve how Resend classifies bounces, deferrals, transient failures, hard failures, and delivery outcomes
Build tools that help the team debug delivery issues by
