System Infrastructure Administrator

Sebastian Hałaczkiewicz

Systems Administrator specializing in the Microsoft Environment and enterprise-grade high-availability infrastructure.

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Microsoft Ecosystem Expertise

Windows Server

Deep expertise in OS maintenance, security patching, and role-based configuration.

Active Directory

IAM, Group Policy management, and Domain Controller health monitoring.

Azure Cloud

Management of virtual networks, cloud identities, and hybrid infrastructure scaling.

Infra Management

Platform operations monitoring, PowerShell automation, and incident response.

Professional Path

A journey through technical excellence and enterprise evolution.

Current Role

Customer Service Support Engineer

Etteplan (for Fortum) • 2026 — Today

Focus on high availability infrastructure, Active Directory, and Azure cloud path. Integrated environment management with Datadog monitoring to ensure maximum service uptime and performance.

L2 Customer Support Agent

GR8 Tech • 2024 — 2026

Built the L2 support team from scratch, establishing foundational operational policies and comprehensive technical documentation. Responsible for high-level ticket analysis and creating Jira dashboards and filters to optimize team workflow.

2nd Line Support Analyst/Engineer

Atos Poland (for Ministry of Justice UK) • 2022 — 2023

Specialized in Active Directory administration, complex NTFS permission management, and Microsoft Intune device enrollment. Managed user accounts, mailboxes via Exchange, and maintained Office 365 cloud environments.

Banking Systems Administrator

Credit Agricole Bank Polska S.A. • 2021 — 2022

Management of MS SQL Servers and administration of Pivotal CRM application. Supported debt collection processes, performed deployment of new software versions, and provided advanced troubleshooting for Pivotal application issues.

IT Specialist / System Administrator

Nestle Polska / Nestle Purina • 2016 — 2021

End-to-end infrastructure management: Windows Servers (2008R2/2016), VMware (ESXi, 3PAR storage), MS SQL databases, and Cisco network environments. Also managed CCTV systems (Analog/IP) for enterprise security.

Systems Administrator

Sky IT (for Dongseo Display & Pantos Logistics) • 2015 — 2016

Infrastructure and network administration, including administration of computer networks, workstations, and peripherals. Managed network resources and supervised CCTV systems for logistics operations.

Hardware & Systems Diagnostics Specialist

PHU TELDOM • 2013 — 2015

Expert diagnosis and repair of PC/laptop hardware and software systems. Conducted high-precision testing and maintenance of electronic components to ensure optimal performance and longevity.

Connect with me

Available for professional discussions on Microsoft Infrastructure, Platform Operations, and enterprise architecture.

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