Senior Systems Engineer - Email Deliverability & Infrastructure
We are seeking a highly technical, impact-driven Senior Systems Engineer to own, scale, and protect our core email transmission infrastructure.
In this role, your golden rule will be Reputation Above All.
You are not just managing email lists or monitoring dashboards; you will architect and maintain the high‐availability server infrastructure, Mail Transfer Agents (MTAs), and automated defensive systems that ensure our legitimate traffic hits the inbox while bad actors are ruthlessly contained.
The ideal candidate bridges the gap between deep Linux systems administration, network engineering, and advanced email deliverability strategy.
You will have a massive impact on the company by safeguarding our global IP/domain reputation, minimizing blast radiuses, and ensuring zero‐downtime mail operations across our entire infrastructure network.
Location: Fully Remote (Global)
Compensation: $24k to $36k USD Yearly
Position Type: Full‐Time Contract
Role Overview
We are seeking a highly technical, impact‐driven Senior Systems Engineer to own, scale, and protect our core email transmission infrastructure.
In this role, your golden rule will be Reputation Above All.
You are not just managing email lists or monitoring dashboards; you will architect and maintain the high‐availability server infrastructure, Mail Transfer Agents (MTAs), and automated defensive systems that ensure our legitimate traffic hits the inbox while bad actors are ruthlessly contained.
The ideal candidate bridges the gap between deep Linux systems administration, network engineering, and advanced email deliverability strategy.
You will have a massive impact on the company by safeguarding our general IP/domain reputation, minimizing blast radiuses, and ensuring zero‐downtime mail operations across our entire infrastructure network.
Core Responsibilities
1. Infrastructure Management & High Availability
MTA Optimization: Maintain and configure core MTAs (Postfix, Postal) and IMAP/POP3 servers (Dovecot), ensuring graceful reloads over restarts to prevent dropping active connections.
Traffic Routing & Load Balancing: Utilize HAProxy and network routing protocols (like BGP via FRRouting) to distribute outbound traffic and architect high‐volume failover mechanisms.
Redundancy & Failover: Administer backend infrastructure databases (PostgreSQL replica setups) and maintain dedicated "Block" backup/archive servers to instantly take over the workload of a failed primary "Cube" server.
Architectural Segregation: Maintain strict workload isolation across our infrastructure network—separating standard nodes for mail stacks, specialized injection nodes (Postal), and separate archiving/backup systems to prevent high‐volume senders from degrading performance.
2. Deliverability Engine & Authentication Protocol Architecture
Protocol Enforcement: Act as the absolute technical authority on DNS and authentication setups, maintaining flawless configurations for SPF (navigating the 10‐lookup limit), DKIM (key rotation and forwarding protection), DMARC (safely driving policies toward p=reject), and BIMI.
Traffic Throttling: Implement automated, MTA‐level dynamic throttling to handle 4xx deferrals instantly, preventing a single high‐volume sender from triggering global rate limits across our shared IP pools.
Warm‐up Strategy: Design and guide automated IP/Domain Warm‐up Plans for new infrastructure, managing incremental volume scaling over 2–4 week cycles.
3. Edge Security, Anti‐Abuse & Incident Response
Outbound Spam Filtering: Configure and optimize Rspamd to actively scan, flag, and quarantine highly spammy content before it exits our network.
Edge Defense: Deploy automated connection‐dropping systems (Fail2Ban, custom SMTP blocker scripts) to mitigate authenticated attacks, brute‐force attempts, and malicious traffic.
Blast Radius Mitigation: Program and maintain a dynamic IP pooling engine ("The Penalty Box") to instantly isolate accounts displaying poor metrics (bounces, FBL spikes) away from prime Tier‐1 IP pools.
Blocklist Remediation: Act as the primary responder to major DNSBL (e.g., Spamhaus) listings.
Leverage log analysis to locate the root cause account, plug the security leak, and submit expert delisting requests.
4. Observability & Monitoring
Log Shipping Architecture: Build and manage high‐performance log aggregation pipelines using Vector to ship system and MTA data into a centralized repository for real‐time auditing and incident response.
Network Auditing:



Utilize IPAudit and custom tools to continuously scan for bandwidth anomalies, connection spikes, or compromised user credentials.
Dashboard Management: Actively monitor ISP infrastructure portals daily (Google Postmaster Tools, Microsoft SNDS, Yahoo Sender Hub) along with third‐party tracking tools (GlockApps, Validity/ReturnPath, MXToolbox, DMARCian).
Requirements
Must‐Have Technical Stack & Skills
Systems Engineering Background: 5+ years of experience as a Linux Systems Administrator, DevOps, or Infrastructure Engineer with deep networking knowledge (TCP/IP, routing, ports, DNS management).
MTA Mastery: Expert‐level proficiency configuring, debugging, and optimizing enterprise mail tools such as Postfix, Dovecot, or Postal.
Security & Filtering: Hands‐on experience writing rules and maintaining mail‐filtering/anti‐abuse applications like Rspamd and Fail2Ban.
Observability Pipelines: Proven experience building or maintaining log pipelines using Vector or similar high‐scale telemetry frameworks.
Infrastructure Automation: Experience implementing network routing layer tools (HAProxy, FRRouting) and relational databases (PostgreSQL replication).
Certificate Management: Strong familiarity with automated SSL/TLS certificate rotation and multi‐node compliance monitoring to ensure broken TLS never causes silent drops.
Deliverability & Operational Standards
Deep comprehension of the difference between Delivery (server handoff) and Deliverability (inbox placement).
Expert parsing of aggregate DMARC reports using platforms like DMARCian, Valimail, or Postmark.
Strict commitment to Acceptable Use Policies (AUP): zero tolerance for purchased/scraped lists and a firm grasp on Feedback Loop (FBL) automated triage.
Key Performance Indicators (KPIs)
Your success in this role will be directly measured by your ability to keep our infrastructure metrics pristine:
Integral Infrastructure Spam Complaint Rate: Maintained strictly under 0.1%.
Global Hard Bounce Rate: Kept consistently below 2.0%.
Infrastructure Uptime: *****% availability across all outbound MTAs and mail relays.
Incident Isolation Time: Transitioning high‐risk or abusive senders to the "Penalty Box" or circuit‐breaking campaigns within minutes of a threshold breach.
Benefits
This is a highly technical systems engineering role, not a marketing or email campaign management position.
To be considered, you must have hands‐on experience configuring Linux mail servers at the command‐line level.
Please confirm upon applying that the compensation range of $24,000 to $36,000 USD per year aligns with your expectations.
Job Description
Identifies opportunities for others to replace or upgrade server components.
Validates cabling, checking network environment build and connectivity is established.
Monitors and assigns work in ticketing environment, mentoring less experienced technicians or implementing technical solutions.
Trains advance fix and repair techniques that align with corporate objectives and adheres to standard operating procedures (SOPs) and method of procedures (MOPs) for operational Data Center Change Control processes.
Acts as a technical liaison for technical and non‐technical teams, providing subject matter expertise to identify and resolve resiliency, reliability, and availability risks.
Responsibilities
Identifies opportunities for other team members to work with of servers and server components and main hardware to ensure efficient performance for its entire lifecycle.
Guides and coaches less experienced technicians on best practices for the power distribution units and/or replacement hardware, removing and troubleshooting hardware without disturbing critical infrastructure, as needed.
Guides and instructs less experienced technicians on best practices for implementing –designed and defined network communications and solutions, signing off on client configurations within environments.
Validates cabling, checking network environment build and connectivity is established, verifying that devices are connected and error free.
Monitors and assigns work in ticketing environment,



mentoring less experienced technicians or implementing technical solutions to enhance and/or troubleshoot the system within Service Level Agreements (SLAs) against assigned ticket, potentially identifying and escalating trends, and documenting steps or resolutions involved in maintaining the environments.
Oversees adherence to all established Standard Operating Procedures (SOPs)/Maintenance Operation Protocols (MOPs) when performing tasks, ensuring all work stays in sync with site rules, colocation vendor rules, and signs‐off within a data center and/or customer site environments.
Upholds and ensures established security procedures, considering applicable local regulations, conducting functional testing of security.
Ensures compliance with health and safety guidelines (including personal protection equipment, site access, or specific data site compliance) during on‐site work at customer locations and at office, with limited supervision.
Continuous Improvement
Trains advance fix and repair techniques that align with corporate objectives and adheres to SOPs and MOPs for operational Data Center Change Control processes.
Identifies repeating problems or trends, escalating issues to senior peers and/or external experts, operations team, and engaging global team about local issues.
Analyzes issues for repeating problems or trends, escalating identified issues to external experts and operations team, and engaging global team about local issues.
Collaboration, Vendor Relations, and Leadership
Leads collaboration efforts with project teams/colocation partners to properly test and validate the installation, operation, and performance of electrical/mechanical systems and coordinate site utility requirements.
Acts as a technical liaison for technical and non‐technical teams, providing subject matter expertise to identify and resolve resiliency, reliability, and availability risks.
Ensures contractors and vendors deliver quality services and that all SLAs are being met.
Contributes to quality assurance through process creation and training of less experienced peers.
Core Responsibilities
Completes complex and/or ambiguous tasks in accordance with project requirements, with limited instructions.
Provides guidance to team members on shifting priorities and resources according to team needs.
Collaborates across teams to lead the delivery of impactful work and provide support for critical team objectives.
Leverages advanced understanding of business, stakeholder, and/or customer needs to build partnerships within and outside of team.
Develops and shares procedures to identify and resolve routine or non‐routine issues, serving as an escalation point for the team.
Collects and reviews data and/or information to troubleshoot complex errors.
Embraces continuous learning by actively seeking to build knowledge and learning new skills and/or tools and staying current with trends and best practices in one's field.
Seeks out and leverages feedback and advanced training to improve skills.
Recommends, implements, and shares improvements to improve the efficiency and effectiveness of complex processes, protocols, and workflows.
Career Level - OP4
About Us
Only Oracle brings together the data, infrastructure, applications, and expertise to power everything from industry innovations to life‐saving care.
And with AI embedded across our products and services, we help customers turn that promise into a better future for all.
Discover your potential at a company leading the way in AI and cloud solutions that impact billions of lives.
True innovation starts when everyone is empowered to contribute.
That's why we're committed to growing a workforce that promotes opportunities for all with competitive benefits that support our people with flexible medical, life insurance, and retirement options.
We also encourage employees to give back to their communities through our volunteer programs.
We're committed to including people with disabilities at all stages of the employment process.
If you require accessibility assistance or accommodation for a disability at any point, let us know by emailing or by calling in the United States.
Oracle is an Equal Employment Opportunity Employer
All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, national origin, sexual orientation, gender identity, disability and protected veterans' status, or any other characteristic protected by law.
Oracle will consider for employment qualified applicants with arrest and conviction records pursuant to applicable law.
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