Backend Engineer (MTA), Core Sending

<p style="min-height:1.5em">Resend is growing fast, and there are now over 2 million developers using it. As the Core Sending Squad, we are responsible for building and maintaining the core components of Resend that handle sending transactional and marketing emails.</p><p style="min-height:1.5em">This role is fully remote-based in Americas or European time zones, with some expected travel for team off-sites, conferences, meetups, and more.</p><p style="min-height:1.5em"><a target="_blank" rel="noopener noreferrer nofollow" href="https://resend.com/handbook"><strong>Read more about how we work, how we hire, and what we value here</strong></a>.</p><p style="min-height:1.5em"></p><h2><strong>In this role, you will…</strong></h2><ul style="min-height:1.5em"><li><p style="min-height:1.5em">Build and operate Resend’s email transport infrastructure</p></li><li><p style="min-height:1.5em">Work on SMTP delivery, MTA systems, routing, retries, backoff strategies, and delivery controls</p></li><li><p style="min-height:1.5em">Design systems for domain-level, provider-level, customer-level, and IP-level throttling</p></li><li><p style="min-height:1.5em">Build infrastructure for shared IP pools, dedicated IPs, warmup execution, and reputation-aware routing</p></li><li><p style="min-height:1.5em">Improve how Resend classifies bounces, deferrals, transient failures, hard failures, and delivery outcomes</p></li><li><p style="min-height:1.5em">Build tools that help the team debug delivery issues by customer, domain, mailbox provider, route, IP, message type, and event</p></li><li><p style="min-height:1.5em">Help design systems that make sending behavior safer, more observable, and easier to operate</p></li><li><p style="min-height:1.5em">Translate reputation strategy into backend systems</p></li><li><p style="min-height:1.5em">Partner with Trust &amp; Safety to build controls that protect Resend’s sending network from abuse</p></li><li><p style="min-height:1.5em">Participate in incident response for sending, provider, and deliverability-sensitive issues</p></li><li><p style="min-height:1.5em">Be on-call for critical services</p></li></ul><p style="min-height:1.5em"></p><h2><strong>You will be a great fit if you...</strong></h2><ul style="min-height:1.5em"><li><p style="min-height:1.5em">Have strong backend engineering experience</p></li><li><p style="min-height:1.5em">Have worked on email, messaging, notifications, communications, infrastructure, or other high-volume delivery systems</p></li><li><p style="min-height:1.5em">Understand queues, workers, retries, idempotency, rate limits, backpressure, and distributed systems</p></li><li><p style="min-height:1.5em">Have experience or strong interest in SMTP, MTAs, DNS, bounces, deferrals, DNS, IP pools, and mailbox-provider behavior</p></li><li><p style="min-height:1.5em">Care about reliability, observability, operational excellence, and reducing blast radius</p></li><li><p style="min-height:1.5em">Have low ego, high ownership, and strong taste for simple systems</p></li></ul><p style="min-height:1.5em"></p><h2><strong>You will be an exceptional fit if you also...</strong></h2><ul style="min-height:1.5em"><li><p style="min-height:1.5em">Have experience working on applications with a high workload</p></li><li><p style="min-height:1.5em">Know about email best practices, or are <strong>willing to learn more about this space</strong></p></li><li><p style="min-height:1.5em">Are experienced in <strong>Typescript</strong> and <strong>Golang</strong></p></li></ul><h2><strong>What it means to join the team:</strong></h2><ul style="min-height:1.5em"><li><p style="min-height:1.5em">Autonomy to "just ship it"</p></li><li><p style="min-height:1.5em">100% remote team with flexible working schedules</p></li><li><p style="min-height:1.5em">Modern tech stack (Typescript, AWS, Go, Postgres, Datadog)</p></li><li><p style="min-height:1.5em">Honest and low-ego team</p></li><li><p style="min-height:1.5em">Ownership of problems and solutions</p></li><li><p style="min-height:1.5em">Comp: $150,000 - $170,000 USD, commensurate with experience</p></li></ul><h2></h2><h2><strong>About Resend</strong></h2><p style="min-height:1.5em">We are building the modern email sending platform for developers. We care deeply about quality, craft, and the developer experience.</p><p style="min-height:1.5em">Our fully remote team of 45 spans 13 countries and counting. We're backed by a16z, Y Combinator, and others. <a target="_blank" rel="noopener noreferrer nofollow" href="https://resend.com/humans">Meet the humans →</a></p>