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 general 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 global IP/domain reputation, minimizing blast radiuses, and ensuring zero-downtime mail operations across our entire infrastructure network.
Core Responsibilities
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:
Global 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.
OnsiteBuenos Aires, Ciudad Autónoma de Buenos Aires, ArgentinaFull timeR*****Careers that change lives start here.
Medtronic is a global leader in healthcare technology with a Mission to alleviate pain, restore health, and extend life.
Our 95,000 employees work across more than 150 countries to put patients first - developing innovative medical technologies that improve the lives of 72+ million patients each year.
Your unique talents will help shape the future of healthcare while building a career grounded in purpose, growth, and impact.A Day in the LifeSomos líderes en tecnología y soluciones médicas impulsados por una misión, con un legado de integridad e innovación.
Trabaja con nosotros para incentivar una mejor atención al paciente y colabora con toda la industria para que la asistencia sanitaria sea más asequible y accesible.
Forma parte de una comunidad de expertos comprometidos con garantizar una asistencia sanitaria de calidad y asequible en todo el mundo.Venga a fortalecer sus habilidades especializadas y a mejorar su experiencia.
Le apoyaremos con la formación, la tutoría, la orientación y las redes que necesita para avanzar, y le capacitaremos para que trabaje de la manera que más le convenga.
Juntos, podemos afrontar los retos que cambiarán el panorama de la asistencia sanitaria.
Únase a nosotros para desarrollar una carrera que cambia vidas.
El puesto estará ubicado en Capital Federal / Gran Buenos Aires en un modelo flexible.Las responsabilidades pueden incluir las siguientes y se pueden asignar otras tareas:+ Identifica, desarrolla y aplica estrategias empresariales a corto y largo plazo relacionadas con el desarrollo de nuevos productos, tecnologías, servicios, productos derivados y/o sectores.
+ Identifica mercados y oportunidades de concesión de licencias, y determina la viabilidad del desarrollo empresarial y de productos.
+ Realiza análisis económicos sobre oportunidades de productos nuevos o mejorados.
+ Desarrolla modelos de negocio y determina las tendencias del mercado para fundamentar las perspectivas a largo plazo.
+ Coordina con los departamentos internos la identificación y la implementación de proyectos de desarrollo empresarial.
+ Puede colaborar con los equipos de ventas, marketing y clientes potenciales para determinar sus necesidades.
+ Desarrolla y difunde información de forma continua a todas las partes pertinentes sobre el cumplimiento de las metas y los objetivos del proyecto.Conocimientos y experiencia requeridos:+ Carrera Técnica concluida de Instrumentista Quirúrgico+ Un año de experiencia laborando en ambientes hospitalarios y/o empresas de dispositivos médicos+ Experiencia entrando a quirófano+ Sería una ventaja contar con un nivel de inglés Intermedio+ Sería una ventaja contar con experiencia en portafolios de dispositivos médicos de sala de operaciones / quirúrgicos+ Sería una venta contar con experiencia comercial / ventas de dispositivos médicos / Farmacéuticos+ Ubicación del puesto: Capital Federal / Gran Buenos AiresPhysical Job RequirementsThe above statements are intended to describe the general nature and level of work being performed by employees assigned to this position, but they are not an exhaustive list of all the required responsibilities and skills of this position.
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