HamsterOS — Mean Hamster Software
← ProductsOS<br>HamsterOS<br>Coming November 2026v.57<br>FreeDOS-backed boot · VM86 DOS first pass · cooperative desktop · 386+ / 2 MB<br>A complete 32-bit desktop OS on a single 1.44 MB floppy. The current master image boots through a trimmed FreeDOS wrapper, launches the 32-bit HamsterOS kernel with HAMLOAD.EXE, and runs a real windowed desktop on 386/486-era hardware. It can also install to and boot from an ATA hard disk via INSTALL.APP.
Press<br>HamsterOS on Hackaday<br>Hackaday featured HamsterOS in Donald Papp's June 29, 2026 article covering the 1.44 MB floppy desktop, built-in apps, hard-disk install path, DOS support, and HamsterWeazle.<br>Read the Hackaday feature →<br>Screenshots<br>Boot screen
Welcome screen and file browser
Desktop with Control Panel display preferences
Desktop Shell<br>A complete windowed GUI running entirely within 1.44 MB.<br>Window Manager<br>Full z-order stacking with resizable and draggable windows. Bounded damage redraws on focus changes. Active windows show a navy title bar; inactive windows show dark gray.
Launcher Toolbar<br>Ten visible slots per page with pagination. 16-colour palette-indexed pixel-art icons with hover raise and pressed-state offset. Slots for FILES, FIND, NOTE, CLOCK, PREFS, CALC, CAL, PAINT, GAMES, APPS, TOOLS, USER, PIANO, and CD Player.
File Browser<br>Up to 5 spatial windows at once. Icon view (52x40) and list view, sorted by Name, Type, Size, or Date. Per-type icons for folders, documents, images, executables, and scripts. Copy/paste, rename, delete, new folder, mouse-wheel scrolling, and progress toasts on reads and writes.
Menu Bar<br>Classic File/Edit/View/Special menu bar always visible. Hover switches open menus; stale pixels cleared on close. Alt+F/E/V/S keyboard access.
Find Files<br>Recursive filename search with a dynamic drive selector showing only mounted drives. Click a result to jump the file manager. Light-dismiss on outside click.
Desktop<br>Dynamic drive icons for mounted floppies, hard disks, optical media, and the RAM disk, with 3D bevel selection. Desktop file positions save to DESKTOP.CFG, and removable icons appear automatically when drives mount.
Trash<br>Delete operations move files and folders into boot-volume /TRASH/ with restore metadata. The desktop Trash icon opens the folder, restores items, or empties hard-deleted contents.
Screen Savers<br>Stars (parallax), Flying Hamsters (16-colour animated sprites with bobbing and wing-flap), and Text Bounce. Configurable idle timeout; any input wakes.
System Recovery<br>CMOS crash counter forces VGA 640x480x16 safe mode after 3 consecutive crashes. I/O stall detection surfaces a nonfatal dialog if the main loop heartbeat stalls over 8 seconds.
Cooperative Multitasking<br>One lean foreground event loop dispatches queued input, bounded redraws, app update ticks, and kernel_service() yield points so slow disks stay responsive without RAM-heavy preemptive stacks.
Applications<br>All built-in, all fit on the floppy.<br>Notepad<br>Load, Save, Save As with FAT file dialog. 4-step undo, Find and Replace (case-insensitive, with highlight), line numbers, word and character count, Go-to-line (Ctrl+G). Dirty tracking with confirm-before-close.
HamsterPaint<br>Full-screen 16-colour BMP editor. Pencil, fill bucket, line, rectangle, ellipse, eraser, selectable regions, cut/copy/paste, Ctrl+Z undo, Ctrl+S save, and 1x/2x zoom.
Image Viewer<br>Standalone IMGVIEW.APP opens BMP and GIF files from the toolbar, launcher, file dialog, or file associations. Images are quantized into the VGA/EGA 16-colour palette.
HamsterPiano<br>On-screen keyboard. When SoundBlaster 16 is detected, plays OPL3 FM notes and shows a DEMO button for The Entertainer. Falls back to PC speaker square-wave tones otherwise.
CD Audio Player<br>Red Book audio via Matsushita/MKE ISA CD-ROM or ATAPI. Track listing, elapsed time, play, pause, stop, and skip.
Clock, Calendar, Calculator<br>RTC-driven analog clock with second hand. Monthly calendar with highlighted current date. Four-function calculator.
Preferences<br>Control Panel tabs for Desktop, Theme, Mouse, Sound, Display, screen savers, RAM disk, font choice, and direct CMOS time/date editing.
Games<br>Eight native games plus classic DOS titles through VM86 first, with FreeDOS handoff fallback.<br>FreeCell<br>52-card solitaire with auto-move, multi-card run moves, and single-level undo.
Video Poker<br>Jacks or Better 5-card draw. Full hand evaluator, coin balance, payouts up to 800x.
Minesweeper<br>Left-click reveal, right-click flag, win/lose detection.
Snake<br>Arrow-key growth, collision, persistent top-5 scores, initials, and RTC date stamps.
Sliding Puzzle<br>15-tile with solved detection.
Moon Lander<br>Gravity, thrust, and fuel gauge.
Slot Machine<br>Three reels, paylines, and coin mechanics.
DOS Games<br>File-manager .COM/.EXE launches try the in-kernel VM86 DOS box first. Broader programs can still fall back to FreeDOS.
Storage<br>FAT12/16/32 read/write, ISO-9660 read-only, RAM disk, and a full install...