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Oldzhay S.OS

Oldzhay S.

Supermalter

Fractional CTO/IT Architect/IT Security/Linux

€402/day
48 projects
Madrid, ES
15+ years

Average response time: 1 hour

About Oldzhay

Passionate about IT security and IT system architecture, I possess over two decades of expertise in designing, implementing and managing robust server infrastructure, firewalls, load-balancers, networking and email systems.

With a rich real-world working experience spanning seven diverse industries - Fintech, IT, Banking, Marketing, E-commerce, Online News and Internet Service Providers - I bring a comprehensive understanding of the unique challenges and requirements of each sector.

Throughout my career, I have consistently delivered high-quality solutions in servers, networking, firewall management, load balancer optimization, and VPN implementation. I excel in real-time monitoring and IT security practices, ensuring organizations stay protected against evolving threats.

Driven by collaboration, I thrive in fast-paced environments where I can leverage my skills to drive innovation and deliver exceptional results.

Together, we can navigate the ever-changing IT landscape and achieve success.

If you have a project in mind, let's engage in a conversation to discuss how I can contribute to your organization's IT goals.

  • Bulgarian

    Native or bilingual

  • English

    Fluent

  • Spanish

    Native or bilingual

Can work on-site
Madrid (up to 50km)

Experience

  • Saroolu IT Security Tech
    Founder
    August 2010 - Today (15 years and 10 months)
    • Diseño y despliegue de infraestructuras Linux, VMware y Proxmox.
    • Dirección técnica y roadmap tecnológico para startups y pymes.
    • Optimización de operaciones IT, proveedores y costes.
    • Refuerzo de la seguridad y resiliencia de sistemas críticos.
    • Definición de estándares técnicos y asesoramiento continuo como CTO fraccional.
    Linux VMWARE Arquitectura IT CTO Containerization and Virtualization
  • BNP Paribas CIB
    Senior System Administrator
    October 2015 - August 2022 (6 years and 10 months)
    Madrid, Spain
    Garantizé la estabilidad, seguridad y rendimiento de entornos Linux críticos en el sector bancario, asegurando la continuidad del negocio y el cumplimiento de los estándares corporativos globales.

    • Administración de sistemas y monitorización de rendimiento en entornos Linux Red Hat.
    • Aplicación de parches de seguridad, gestión de incidencias y documentación técnica.
    • Coordinación con usuarios y equipos globales para mantener niveles óptimos de servicio.
    • Soporte de nivel 2, gestión de data center (servidores, redes, almacenamiento) y relación con proveedores.

    Keywords: Linux RedHat, Hardware, Security patching, Incident management, ServiceNow, Kibana, Storage, LUN, Veritas Cluster, AD/Centrify.
    Linux Cybersecurity Incident Management Hardware ServiceNow
  • Tink AB (a Visa Solution),
    Senior System Administrator
    August 2022 - March 2023 (7 months)
    Madrid, Spain
    Aseguré la continuidad y seguridad de la infraestructura híbrida de Tink durante una fase crítica de integración con Visa.

    • Migración, mantenimiento y hardening de entornos Linux y VMware ESXi.
    • Administración de firewalls Cisco ASA y cumplimiento QWAC/QSEALC.
    • Monitorización y trazabilidad con Zabbix y Kibana.
    • Documentación técnica y gestión de hardware para servidores y redes.

    Keywords: Linux, VMware, Cisco ASA, Security patching, SSL, Zabbix, Kibana.
    Linux Firewall VMWARE Cisco ASA

Reviews

4,6

Out of 4 ratings

J

Jordi

. - Aubay_Barcelona

Reviewed on 16/03/2026

Oldzhay has chosen to hide 1 review

1 written review is private.

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