Backend Engineer, MTA

Role overview A fully remote engineering team operating in European and Americas time zones is hiring a Backend Engineer to build and operate the email transport infrastructure behind a developer-focused sending platform serving millions of users. The work spans MTA systems, SMTP delivery, routing, retries, throttling, and reputation-aware controls, with on-call responsibility for critical services.

Responsibilities - Build and operate email transport infrastructure including SMTP delivery, MTAs, routing, retries, backoff strategies, and delivery controls - Design throttling and rate-limiting across domain, provider, customer, and IP levels - Build infrastructure for shared IP pools, dedicated IPs, warmup execution, and reputation-aware routing - Improve classification of bounces, deferrals, transient failures, hard failures, and other delivery outcomes - Develop debugging tools that surface delivery issues by customer, domain, mailbox provider, route, IP, message type, and event - Partner with trust and safety teams on controls that protect the sending network from abuse - Participate in incident response and share on-call rotation for critical sending services

Requirements - Strong backend engineering experience on high-volume, distributed systems - Familiarity with queues, workers, retries, idempotency, rate limits, backpressure, and distributed-system fundamentals - Hands-on experience or strong interest in SMTP, MTAs, DNS, bounces, deferrals, IP pools, and mailbox-provider behavior - Care for reliability, observability, and reducing blast radius - Low ego, high ownership, and a taste for simple systems - Strong written communication for async, remote collaboration

Nice to have - Experience with applications operating at very high workload - Knowledge of email deliverability best practices, or willingness to learn - Production experience with TypeScript and Golang

Benefits and work setup - 100% remote team with flexible working schedules - Occasional travel for team off-sites, conferences, and meetups - Modern stack including TypeScript, AWS, Go, Postgres, and Datadog - Compensation range of $150,000 to $170,000 USD, commensurate with experience