Alexander K.Private profile: Upwork shows its earnings only to signed-in members, so we check it every few weeks, not daily. MRR here is a rough estimate (Upwork's six-month earnings ÷ months active). Last read Nov 5, 2026.

* Working experience from 1992 as a software developer, system/network administrator, team leader, CTO * Expert in computer hardware and software configuration, troubleshooting, and virtualization (Linux, Windows) * Expert in Ethernet networking, networking protocols, and associated software and hardware (pfSense, Cisco, Nortel, DLink, 3Com, Dell, Lucent, etc.) * Cloud/virtualization platforms (AWS, Oracle Cloud, VMWare, Proxmox, VirtualBox) * Strong knowledge of Internet technologies * Large programming experience (C/C++, Java, HTML, Perl, PHP, shell scripting, SQL) * RDBMS administration experience (Oracle, MySQL, PostgreSQL, MSSQL) * Firewall and security solutions (pfBlocker, Wazuh) * Troubleshooting experience with shared file systems (NFS, Ceph, maintainer of YAS3FS) * Good management skills * Spoken English, fluent technical English reading and writing