A curiosity recently caught our eye—that curiosity is KolibriOS, a super-lightweight, ultra-fast OS designed for legacy PCs with its floppy drive-friendly install size of just 1.44 MB. PerHackaday’s coverage, which drew our attention to YouTuber Michael MJD’s extended video coverage of the operating system, KolibriOS started as a 32-bit fork of MenuetOS in 2004.

Since then, KolibriOS has become widely multi-platform while maintaining a 32-bit focus and becoming lightweight enough to run on any PC with an i585-compatible CPU, 8MB of RAM, and a VESA-compatible video card.

Official screenshot of KolibriOS running various supported games, including the shareware version of Doom.

As those system requirements and the option to install it with storage as minute as a 1.44MB floppy drive indicate, this operating system is explicitly targeted at legacy PC hardware— modern Linux distros are almost certainly a better choice for PCs that aren’t otherwise aged out of features like, say, modern web browsers.

While Michael MJD and much other coverage of this OS is missing footage of its Netsurf web browser, we were able to verify that it’s an elementary browser only suited for the most basic text-based pages and services—modern HTML5 and video playing are a pipe dream on KolibriOS, which makes the “modern” descriptor quite a stretch even though it is still regularly updated.

A Modern OS… on a Floppy Disk?! - YouTube

While I am somewhat critical of various outlets covering Kolibri’s descriptor as a “modern OS,” make no mistake: this is still a seriously impressive technical feat and more than likely the best OS software you can run on legacy PCs specced closer to its minimum requirements than something like Ubuntu.

The OS is written in x86 assembly code, which makes it super fast and responsive, even on old machines. While modern web browsing is a crapshoot, tasks like basic text editing, IRC, and retro gaming should all work quite well—particularly with the live CD version.

Christopher Harper

The most significant difference between the floppy drive version of KolibriOS and the live CD version of KolibriOS is undoubtedly the included game library. On the floppy drive version, you have 26 bundled games, but they’re all very basic 2D titles.

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On the CD version, this library expands to a whopping 55 games, including four 3D “big games,” shareware versions of seminal FPS titlesWolfenstein 3D, Doom, andQuake. The CD version also includes some additional emulators, including DOSBox, and some extra fonts and system themes to boot.

Christopher Harper has been a successful freelance tech writer specializing in PC hardware and gaming since 2015, and ghostwrote for various B2B clients in High School before that. Outside of work, Christopher is best known to friends and rivals as an active competitive player in various eSports (particularly fighting games and arena shooters) and a purveyor of music ranging from Jimi Hendrix to Killer Mike to the Sonic Adventure 2 soundtrack.