HamsterOS fits – HamsterOS, a tiny multitasking 32-bit graphical operating system for 386 and 486-era PCs, is aiming for a November 2026 release. The OS is built to fit entirely on a single 1.44 MB floppy disk, supports DOS, and includes native applications—plus a standout CMO
The floppy drive clicks, the machine powers up, and for a moment you’re back in an era where “booting” could feel like a ritual. With HamsterOS, that ritual is getting a modern upgrade—without changing the limits of the hardware it’s meant to run on.
HamsterOS is being developed for 386 and 486-era PCs, built by John Swiderski. The project is targeting a November 2026 release. The core promise is simple and striking: a tiny. full-featured multitasking 32-bit graphical operating system that fits on a single 1.44 MB floppy disk. It’s designed as a floppy-first OS. but it can also be installed to a hard drive. and it includes a suite of native applications.
Even for retro users who’ve learned to live with quirks. HamsterOS is built around reducing the chances of getting stuck. One feature getting attention is the CMOS crash counter. which automatically forces the system into a basic VGA safe mode after three consecutive failed boot attempts. In other words, instead of letting repeated boot failures spiral, the system steps in with a recovery-oriented fallback.
The OS doesn’t just live inside its own box, either. HamsterOS includes DOS support, keeping compatibility close to the environment retrocomputers are used to. For people who want to experiment. that matters—because the hardest part of early OS tinkering isn’t always the software. It’s getting it onto the right medium without turning the process into a hardware scavenger hunt.
That’s where Swiderski’s related tool comes in. He also released HamsterWeazle. a free graphical front-end for Greaseweazle. the open-source USB device used to make interfacing with old floppy drives easier. If you’re curious about running HamsterOS but don’t already have a working setup to write to a 1.44 MB floppy. Greaseweazle over USB is one way to do it—and HamsterWeazle is aimed at making that path more user-friendly.
HamsterOS is being framed as part of a wider push to make new software practical on vintage hardware. Swiderski’s post also points back to a recent feature on GentleOS. described as a “charming and streamlined graphical OS” aimed at vintage hardware—used as an example of what’s possible when new ideas meet old machines.
For now, the project’s most urgent milestone is the same for anyone building on retro limitations: the calendar. HamsterOS is scheduled for a November 2026 release, with its floppy-first approach and recovery-minded boot behavior already setting expectations for how it intends to feel in daily use.
HamsterOS retrocomputing floppy disk OS 1.44 MB 386 486 graphical operating system DOS support CMOS crash counter VGA safe mode Greaseweazle HamsterWeazle