> loading exhibit_00.dat [OK]
> mounting /museum [OK]
> ready

Museum of
Lost Operating Systems

A permanent exhibition of the rarest software worlds ever built. Some were decades ahead of their time. Some were built by one person. Some still boot today if you know where to look.

▮▮▮▮▮ rarity index (5 = practically mythical)ALIVE maintained todayHOBBY kept breathing by devoteesEXTINCT museum hardware only
Wing I · One-Person Universes

Entire operating systems written, unbelievably, by a single human being. Kernel, compiler, GUI, everything.

TempleOS2005 – 2018
TempleOS V5.03 · Adam.HC
>Cd("/Home");
>Dir;
Adam.HC Once.HC Psalmody.HC
U0 Main() { "Hello!\n"; }
God says: rejoice
>

Terry Davis spent a decade building an entire OS alone: his own kernel, his own compiler, his own language (HolyC), all in 100k lines. He believed it was a divine commission, a third temple made of code. Brilliant, tragic, and unlike anything else in computing history.

Author
Terry A. Davis, solo
Written in
HolyC (his own language)
Size
~100,000 lines, ~16 MB
Constraint
640x480, 16 colors, by design
▮▮▮▮raritycommunity forks
SerenityOS2018 – now
Terminal_×
File Edit View Help
courage@serenity:~$ uname -a
SerenityOS 1.0-dev x86_64
courage@serenity:~$ _

Andreas Kling started it as a daily discipline after leaving rehab, streaming every line on YouTube. The rule: zero third-party code. The whole userland, browser included, was built from scratch. That browser grew up and left home; it's now the independent Ladybird project.

Author
Andreas Kling + community
Written in
C++ (own standard library)
Aesthetic
a love letter to late-90s UI
Famous rule
no outside dependencies
▮▮▮▮▮rarityalive
MenuetOS2000 – now
M64: SysInfo×
CPU: x86_64
RAM: 128 MB
OS size: 1.44 MB
Written in: FASM

A complete graphical operating system written entirely in x86 assembly language. The whole thing, GUI and all, fits inside 1.44 MB. In an era of multi-gigabyte OS installs, Menuet is a monk's demonstration that almost all of that weight is optional.

Author
Ville M. Turjanmaa + team
Written in
pure assembly (FASM)
Footprint
one 1.44 MB floppy
Spawned
KolibriOS (see Wing II)
▮▮▮▮rarityalive
Wing II · The Survivors

Systems the mainstream forgot, kept alive by small crews who refuse to let them die. All of these boot on real hardware today.

Haiku2001 – now
Tracker · /boot/home×
📁 Desktop
📁 mail
📁 config
query: kind == "book"

In the 90s, BeOS was the future: pervasive multithreading, a 64-bit journaling filesystem with database powers, buttery media playback. Apple nearly bought it, chose NeXT instead, and Be died. Haiku is its open-source resurrection, and it is still genuinely pleasant to use.

Ancestor
BeOS (Be Inc., 1995)
Signature
the yellow window tab
Killer trait
filesystem with live queries
Status
beta releases, daily-drivable
▮▮▮▮▮rarityalive
RISC OS1987 – now
×Filer · $.Apps◇ □
▤ !Draw▤ !Paint▤ !Edit▤ !Boot
Acorn · Archimedes · 1987

Built by Acorn for the original ARM processor, which Acorn itself invented. The company that made this quiet beige British desktop accidentally created the CPU architecture now inside nearly every phone on Earth. RISC OS still runs today, happily, on a Raspberry Pi.

Origin
Acorn Computers, UK
Legacy
ARM architecture itself
Quirk
three-button mouse is law
Runs on
Raspberry Pi, today
▮▮▮▮▮rarityalive
KolibriOS2004 – now
System info_ □ ×
Kernel: 0.7.7.0+
Boot: 2.1s
Size: 1.44 MB
ASM: FASM
@panel · 12:04

A fork of MenuetOS and possibly the fastest-booting graphical OS in existence. Power button to full desktop in about two seconds, on ancient hardware. Named for the hummingbird, and it earns it. A vivid reminder of how much waiting we've simply agreed to accept.

Forked from
MenuetOS, 2004
Written in
pure assembly
Boot time
seconds, from cold
Community
largely Russian-speaking
▮▮▮▮rarityalive
Redox OS2015 – now
Terminal×
user@redox:~$ ion --version
redox 0.9.0 · ion shell
user@redox:~$ _

The rare entry that's rare because it's from the future, not the past. A full microkernel OS written in Rust, betting that whole classes of security bugs (the kind that have haunted C-based systems for 50 years) can be designed out of existence at the language level.

Author
Jeremy Soller + community
Written in
Rust, kernel to GUI
Design
microkernel, everything is a URL
Bet
memory safety by construction
▮▮▮▮▮rarityalive
Wing III · The Mythical Vault

The deep archive. Systems that shaped everything you use today and then vanished. Original hardware is collector-grade.

Plan 91992 – ~2015
Newcol Kill Putall Dump Exit | Edit ,
/usr/glenda/hello.rc
#!/bin/rc
echo hello from plan 9
term% cat /dev/mouse
everything is a file

What the creators of Unix built when asked to do it again, properly. Every resource in the system, windows, network connections, even the mouse, is a file you can read and write. Almost nobody ran it, but Linux quietly absorbed its best ideas (/proc, union mounts, UTF-8 itself).

Origin
Bell Labs, Unix team
Gave us
UTF-8, /proc, 9P protocol
Named after
the worst film ever made
Today
9front fork, tiny cult
▮▮▮▮rarity9front fork
ITS1967 – 1990
MIT-AI KA10 ITS 1648
:LOGIN HACKER
MSGS: LAST LOGIN 22:04 EST
no passwords. no protection.
DDT.334
*

The Incompatible Timesharing System, birthplace of hacker culture at MIT's AI Lab. It had no passwords and no file security, as a philosophical statement: information wants to be shared. Emacs was born here. So was much of the culture that later produced open source.

Home
MIT AI Lab, PDP-6/10
Security
none, as philosophy
Birthed
Emacs, hacker culture
Name
a joke about "Compatible" TS
▮▮▮▮▮rarityextinct
Multics1969 – 2000
Multics 12.5, load 12.4/45.0
users = 34
login Smith
Password: ••••••••
You are protected from 47 attacks.
!

The cathedral that Unix was built to escape. Multics invented the hierarchical filesystem, dynamic linking, and serious computer security. Ken Thompson and Dennis Ritchie worked on it, found it too heavy, and wrote a small rebellious system they jokingly named Unix.

Backers
MIT, GE, Bell Labs
Invented
hierarchical filesystem
Hardware
room-sized mainframes only
Final site
Canadian DND, 2000
▮▮▮▮▮rarityextinct
Genera1982 – 1993
Command: Show File FOO.LISP
(defun square (x)
(* x x))
;; compiled in 0.003s
Command:
Zmacs (LISP) FOO.LISP 14:07:26 User Input

The Lisp machine OS that veterans still describe as decades ahead of anything since. The whole system was live, inspectable Lisp: you could open any part of the running OS, edit it, and keep going. Symbolics also held the first .com domain ever registered. Working machines now sell for thousands.

Maker
Symbolics Inc.
Language
Lisp, all the way down
Trivia
symbolics.com, first .com
Hardware
custom Lisp CPUs
▮▮▮▮▮rarityextinct