Backend Engineer, MTA

About the role

Resend is building the most accessible email platform for developers and needs a Backend Engineer to own its Mail Transfer Agent (MTA) infrastructure. You will work remotely with a fully distributed team, focusing on high‑volume email delivery and reliability.

Key responsibilities

• Build and operate Resend’s email transport infrastructure, including SMTP delivery, routing, retries and back‑off strategies.
• Design systems for domain‑level, provider‑level, customer‑level, and IP‑level throttling and reputation‑aware routing.
• Develop infrastructure for shared IP pools, dedicated IPs, warm‑up execution and delivery controls.
• Improve classification of bounces, deferrals, transient and hard failures and create debugging tools for delivery issues.
• Partner with Trust & Safety and Core Sending to protect the sending network from abuse and participate in incident response.

Required profile

• Strong backend engineering experience, preferably with high‑volume delivery systems.
• Experience or strong interest in SMTP, MTAs, DNS, IP pools and mailbox‑provider behavior.
• Understanding of queues, workers, retries, idempotency, rate limits, back‑pressure and distributed systems.
• Commitment to reliability, observability, operational excellence and reducing blast radius.
• Low ego, high ownership and a taste for simple, maintainable systems.

Required skills

• TypeScript
• Golang
• AWS
• PostgreSQL
• Datadog
• SMTP / MTA
• DNS

What we offer

• Autonomy to ship features quickly
• 100% remote work with flexible schedules
• Modern tech stack (TypeScript, Go, AWS, Postgres, Datadog)
• Honest, low‑ego team culture
• Competitive compensation: $150,000‑$170,000 USD per year