Remote Senior Systems Engineer – Email Deliverability

Mission Inbox Inc; United States; Remote; USD 40,000 - 62,000; Full time

Job summary

Mission Inbox seeks a Senior Systems Engineer to own and scale our global email infrastructure. You will architect high-availability MTAs, load-balance traffic, and protect our reputation across regions.

You will drive deliverability strategy, implement SPF/DKIM/DMARC/BIMI, and build automated defenses against abuse. Experience with Linux systems, Postfix/Postal, Dovecot, HAProxy, and vector-based observability is required.

Qualifications

• 5+ years of Linux systems administration / DevOps experience.
• Expert level with MTAs (Postfix, Postal) and IMAP/POP3 servers (Dovecot).
• Experience configuring SPF/DKIM/DMARC/BIMI and DNS.
• Knowledge of Rspamd and Fail2Ban for edge security.
• Observability pipelines using Vector or similar.
• Automation of networking and database replication (PostgreSQL).
• Understand delivery vs. deliverability and SPF rate limits.

Responsibilities

• Maintain high-availability infrastructure for outbound mail and MTAs.
• Configure and optimize DNS authentication and BIMI deployments.
• Implement automated throttling and warm-up plans for IPs/domains.
• Respond to abuse, monitor blocks, and remediate delistings.
• Build log pipelines and dashboards for real-time monitoring.

Skills

Linux systems

DevOps

Networking

Postfix/Dovecot/Postal

HAProxy/FRRouting

Rspamd/Fail2Ban

Vector

PostgreSQL replication

Mail deliverability

Tools

Postfix

Dovecot

Postal

HAProxy

FRRouting

Job description

Mission Inbox seeks a Senior Systems Engineer to own and scale our global email infrastructure. You will architect high-availability MTAs, load-balance traffic, and protect our reputation across regions.

You will drive deliverability strategy, implement SPF/DKIM/DMARC/BIMI, and build automated defenses against abuse. Experience with Linux systems, Postfix/Postal, Dovecot, HAProxy, and vector-based observability is required.