ArozOS turns a small server or single-board computer into a private cloud desktop you open in any browser, with windows, a start menu, and a taskbar instead of a pile of separate admin panels. You sign in at your server address and land on a desktop with a file manager for uploading, downloading, dragging, sharing, and tracking copy progress, plus built-in apps for music, photos, video, notes, recording, timers, a web editor, and a code studio, and you can add more from an index of third-party web applications. Behind the desktop, storage pools combine local disks and remote WebDAV, SMB, and SFTP mounts into one virtual file system with per-group permissions, isolated or shared folders, disk quotas, SMART status, and space analysis, and built-in WebDAV, SFTP, FTP, and legacy directory servers expose those files to other devices on your network. Accounts can sign in through OAuth or LDAP, IP allow and block lists and exponential login delays guard the front door, and system settings cover networking, port forwarding, performance monitoring, appearance, and updates. The system runs on as little as 512 MB of memory, installs from a script or precompiled binary, serves a mobile interface and installable progressive web app for phones and touch screens, and accepts Go and Python modules through a sub-service reverse proxy for teams extending it. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. GPL-3.0 licensed.