Backend Engineer, MTA

AI in this role

Builds and operates high-volume email transport and MTA infrastructure at Resend.

typescriptawsgopostgresdatadog

backend-engineeringsmtpdnsdistributed-systemsinfrastructure

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.

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 customer, domain, mailbox provider, route, IP, message type, and event
Help design systems that make sending behavior safer, more observable, and easier to operate
Translate reputation strategy into backend systems
Partner with Trust & Safety and Core Sending to build controls that protect Resend’s sending network from abuse
Participate in incident response for sending, provider, and deliverability-sensitive issues
Be on-call for critical services

You will be a great fit if you...

Have strong backend engineering experience
Have worked on email, messaging, notifications, communications, infrastructure, or other high-volume delivery systems
Understand queues, workers, retries, idempotency, rate limits, backpressure, and distributed systems
Have experience or strong interest in SMTP, MTAs, DNS, bounces, deferrals, DNS, IP pools, and mailbox-provider behavior
Care about reliability, observability, operational excellence, and reducing blast radius
Have low ego, high ownership, and strong taste for simple systems

You will be an exceptional fit if you also...

Have experience working on applications with a high workload
Know about email best practices, or are willing to learn more about this space
Are experienced in Typescript and Golang

What it means to join the team:

Autonomy to "just ship it"
100% remote team with flexible working schedules
Modern tech stack (Typescript, AWS, Go, Postgres, Datadog)
Honest and low-ego team
Ownership of problems and solutions
Comp: $150,000 - $170,000 USD, commensurate with experience

About Resend

We are building the modern email sending platform for developers. We care deeply about quality, craft, and the developer experience.

Our fully remote team of 50 spans 15 countries and counting. We're backed by a16z, Y Combinator, and others. Meet the humans →

How we rate this

Backend Engineer, MTA at Resend rates 10 out of 100 for how much of the daily work is AI. That makes it Little AI (AI Level 1 of 4). The level is about AI in the job, not seniority.

Classification

Little AI. AI is not part of the work.

●●●● Builds AI80 to 100
●●●○ Works on AI60 to 79
●●○○ Uses AI40 to 59
●○○○ Little AI0 to 39

Levels come from how often the tools, models and workflows of the role are named in the posting itself. Open the description and count.

Prepare for this job

A free preview built only from this posting: what it asks for, what you could be asked in an interview, and how to adjust your resume.

Skills and AI tools this role asks for

Backend EngineeringSmtpDnsDistributed SystemsInfrastructureTypescriptAWSGo

Questions you could be asked

Tell me about a project where backend engineering was part of your work. What did you do?
Tell me about a project where smtp was part of your work. What did you do?
Tell me about a project where dns was part of your work. What did you do?
Tell me about a project where distributed systems was part of your work. What did you do?
Tell me about a project where infrastructure was part of your work. What did you do?

Adapt your resume

List these exact terms on your resume: Backend Engineering, Smtp, Dns, Distributed Systems, and Infrastructure. An applicant tracking system matches the wording, not the idea.
Attach one line of real, concrete experience to at least one of them — a tool named with nothing behind it rarely survives a human read.

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