Backend Engineer - Email Infra (Remote)

Lever, Inc.; Town of Italy (NY); Remote; USD 150,000 - 170,000; Full time

Benefits offered by this job

Fully remote

Competitive salary

Autonomy to ship improvements

Modern tech stack

Off-sites and events

Job summary

Lever, Inc. is seeking a Backend Engineer focused on MTAs and high-volume email infrastructure. You will build, operate, and improve the backend systems that power SMTP delivery, routing, retries, and delivery controls at scale.

You will work in a fully remote role with flexible schedules, collaborating with Trust & Safety and Core Sending teams, and contributing to observable, reliable systems used by millions of users.

Qualifications

• Proven backend experience.
• Experience with high-volume email delivery systems.
• Familiarity with queues, retries, idempotency, rate limits.
• Interest/experience in SMTP, MTAs, DNS.
• Bias for reliability and incident readiness.
• Remote work with distributed teams.

Responsibilities

• Build, operate, and improve email transport and delivery infrastructure.
• Develop systems for SMTP delivery, MTA operations, routing, retries, and delivery controls.
• Design throttling across domains, providers, customers, and IPs.
• Build shared IP pools, warmup, and reputation-aware routing.
• Improve handling of bounces, deferrals, transient failures, hard failures.
• Develop internal tooling to investigate delivery issues across customers and routes.
• Participate in incident response and on-call duties.

Skills

Backend engineering

Email infrastructure

TypeScript

Go

SMTP

MTAs

Distributed systems

Observability

On-call readiness

Tools

AWS

PostgreSQL

Datadog

Job description

Lever, Inc. is seeking a Backend Engineer focused on MTAs and high-volume email infrastructure. You will build, operate, and improve the backend systems that power SMTP delivery, routing, retries, and delivery controls at scale.

You will work in a fully remote role with flexible schedules, collaborating with Trust & Safety and Core Sending teams, and contributing to observable, reliable systems used by millions of users.