Aleksandar V.

Top-ranked Linux Infrastructure and Network Security Specialist with over 15 years of hands-on experience. I have delivered enterprise-grade solutions to clients across multiple industries — 3,000+ hours on Upwork, and I still treat every project like it is the first one. I worked with energy companies, healthcare organizations, fintech platforms, banks, insurance and leasing companies. Some of my work involved GCP cost optimization and SACS-002 compliance for energy sector, zero-breach security implementations for healthcare, and multi-location VPN/firewall solutions for enterprise clients. I am comfortable working with development teams, security specialists, or directly with C-level executives — whatever project requires. My main focus is Linux systems and network security, with strong accent on keeping things stable, secure and well-documented. I have experience with traditional and next-generation firewalls, and I can handle everything from basic routing, switching and ACLs to more advanced stuff like IPS/IDS, inline antivirus, anti-malware, HTTP/HTTPS web filtering, and various VPN types — IPSec (pure or combined with GRE, L2TP), SSL VPN, OpenVPN, WireGuard, client-to-site, site-to-site. What I bring: 15+ years Linux Systems Administration (RHEL, Ubuntu, Debian, Rocky, Alma) 4+ years Cloud Architecture — GCP and AWS, average 30% cost reduction achieved for clients 5+ years Cybersecurity, compliance and vulnerability assessment 4+ years Virtualization — KVM, VMware, Hyper-V, Proxmox LAMP/LEMP stacks, load balancing, high availability, zero-downtime deployments 99.99% uptime track record across all long-term engagements I take security seriously — both technical and business side. I am willing to sign NDA and I treat client data with full confidentiality. If you need someone who will take ownership of your infrastructure and not just execute tickets, feel free to reach me out!