Senior Systems Engineer - Email Deliverability & Infrastructure

About the role

We are looking for a senior‑level Systems Engineer to own, scale, and protect our core email transmission infrastructure. The primary focus is maintaining reputation‑first email delivery while defending against abuse and ensuring zero‑downtime operations.

Key responsibilities

• Design, deploy, and maintain high‑availability MTAs (Postfix, Postal) and IMAP/POP3 servers (Dovecot).
• Implement traffic routing and load balancing with HAProxy and BGP (FRRouting) for outbound mail flow.
• Manage redundancy, failover, and PostgreSQL replica setups, plus dedicated backup/archive servers.
• Enforce DNS and authentication protocols (SPF, DKIM, DMARC, BIMI) and handle key rotation and policy enforcement.
• Develop automated throttling, warm‑up plans, and spam filtering using Rspamd.
• Deploy edge defenses such as Fail2Ban and custom SMTP blocker scripts to mitigate attacks.

Required profile

• Deep experience in Linux systems administration and network engineering.
• Proven track record with email deliverability, reputation management, and large‑scale mail infrastructure.
• Strong problem‑solving skills and ability to design resilient, high‑throughput systems.

Required skills

• Linux
• Postfix
• Postal
• Dovecot
• HAProxy
• BGP
• FRRouting
• PostgreSQL
• SPF
• DKIM
• DMARC
• BIMI
• Rspamd
• Fail2Ban

What we offer

• Fully remote work environment.
• Competitive annual compensation ranging from $50,000 to $72,000 USD.
• Opportunity to shape critical email infrastructure at scale.