AnotherOS 0.9.0 (k2225 / u1559) — September 2026 preview

Released 1 October 2026

⚠️ Read this first: early alpha, use at your own risk

AnotherOS is an early preview, alpha-stage operating system written from scratch. It is unstable, it is not designed for everyday use, and it is not a replacement for the system you rely on.

It can crash, freeze, or lose data at any moment.

Installing it to a disk can corrupt or erase data on that disk, including other operating systems' data, if something goes wrong or a wrong disk is chosen.

Running experimental drivers on real hardware can, in the worst case, damage hardware or leave it in a state that needs a power cycle or a firmware reset.

You use this software entirely at your own risk. It is provided "as is", without warranty of any kind. The authors accept no liability for lost data, damaged hardware, or any other harm. Back up everything you care about before you start, and prefer a virtual machine (QEMU, below) or a spare computer with nothing important on it.

What is this?

AnotherOS is an operating system built from the ground up: its own kernel, its own desktop (Fasadas), its own C library toolchain and its own package manager. It isn't a Linux distribution. It borrows hardware drivers from Linux through a compatibility layer, but everything else is its own.

This download is a live image. Boot it from a USB stick or in a virtual machine and you get the full desktop straight away, running from memory, without touching your disks. Nothing is installed unless you run the installer yourself.

Highlights of this release

For the full story, with anecdotes, read the September activity report. In short:

A new supported laptop: the 12" MacBook (2017). It boots, dual-boots next to macOS (hold Option at power-on), runs the desktop at Retina sharpness, and has working WiFi, screen and keyboard brightness, volume keys with macOS-style on-screen indicators, the Caps Lock light, and the microphone.
GPU acceleration on newer Intel graphics (6th–7th generation Core "Skylake/Kaby Lake" era): real hardware OpenGL, GPU video decoding, and hardware-accelerated page drawing in Firefox.
WiFi that stays connected, with a much more robust network stack: downloads survive lost packets, and DNS and addresses follow your network automatically.
Sound mixing: several apps can play at the same time, with a volume slider per app.
Desktop: notifications and a Notification Centre, trackpad gestures, a smarter Finder (copy/move/Trash, clipboard, quick-look previews, network shares), and a desktop that no longer slows down the longer it runs.
Installer: install alongside macOS or Windows from the graphical installer, without erasing the disk.
Windows apps: more Windows programs run directly on the desktop, with internet access, sound and the standard Windows dialogs.
Kernel: working power button, USB serial adapters, faster file reads, and a fix for a rare but serious disk bug.

What do "k2225" and "u1559" mean?

Every AnotherOS build carries three labels:

Label	Example	What it means
Version	`0.9.0`	The product version. It changes rarely, at milestones.
Kernel build	`k2225`	The build number of the kernel, the core of the system that talks to the hardware: memory, processes, disks, drivers. Every kernel the project builds, including internal test builds, takes the next number, so gaps between releases are normal. A bigger number is always a newer kernel.
Userspace build	`u1559`	The build number of the userspace (also called userland): everything above the kernel, meaning the desktop, apps, libraries, installer and command-line tools. It's counted separately from the kernel.

The two numbers are independent counters. k2225 and u1559 aren't meant to be compared with each other. Each one only tells you how new its own half of the system is. The kernel is often rebuilt without the desktop changing, and the other way round, which is why the numbers drift apart.

Where you'll see them:

The About This PC window on the desktop.
The aversion command in a terminal.
uname -a or cat /proc/version, which show the kernel build as #2225.
In the package manager, the kernel and core system packages carry the same number as the last part of their version, so kernel 0.9.0.2225 is k2225.

If you report a bug, please include both numbers. They say exactly which build you were running.

Download

File	What
`k2225-u1559-anotheros-x86_64.zip`	The live image, zipped. Inside: `k2225-u1559-anotheros-x86_64.iso` (1,288,198,144 bytes).
`k2225-u1559-anotheros-x86_64.iso.sha256.txt`	The ISO's SHA-256 checksum.

The ISO is shipped inside a .zip because the download server doesn't accept .iso attachments. Unzip it first. balenaEtcher can also flash the .zip directly.

SHA-256 of the ISO:

0d57a7e2513df6e32494256cdcebdefc872f7b9d9dc6ea62998489bad54324ca  k2225-u1559-anotheros-x86_64.iso

Check it after unzipping. A corrupted download causes very confusing problems.

Linux: sha256sum k2225-u1559-anotheros-x86_64.iso
macOS: shasum -a 256 k2225-u1559-anotheros-x86_64.iso
Windows (PowerShell): Get-FileHash .\k2225-u1559-anotheros-x86_64.iso -Algorithm SHA256

Requirements

A 64-bit x86 PC or Intel Mac (x86_64). No ARM, so no Apple Silicon Macs.
4 GB of RAM recommended. The live system runs from memory.
For USB: a stick of 2 GB or more, and everything on it will be erased.
Works with both classic BIOS and UEFI. Turn Secure Boot off on UEFI PCs, because the boot loader isn't signed.

Option 1 (recommended): try it in QEMU

A virtual machine is the safest way to try AnotherOS: nothing on your computer can be touched.

Install QEMU

Linux (Debian/Ubuntu): sudo apt install qemu-system-x86 ovmf
Linux (Fedora): sudo dnf install qemu-system-x86 edk2-ovmf
macOS (Homebrew): brew install qemu
Windows: the installer from https://qemu.weilnet.workers.dev/ (linked from qemu.org), then run the commands from its folder in PowerShell.

Boot the live image

The basic command works everywhere:

qemu-system-x86_64 -m 4G -smp 2 \
  -cdrom k2225-u1559-anotheros-x86_64.iso \
  -nic user,model=e1000 \
  -device qemu-xhci

On Linux, add -enable-kvm -cpu host. With hardware virtualisation it runs many times faster. On Intel Macs use -accel hvf instead, and on Windows -accel whpx (it needs the Windows Hypervisor Platform feature turned on). Without acceleration it still works, just slowly.

With sound, on a Linux PulseAudio or PipeWire desktop:

qemu-system-x86_64 -enable-kvm -cpu host -m 4G -smp 2 \
  -cdrom k2225-u1559-anotheros-x86_64.iso \
  -nic user,model=e1000 \
  -device qemu-xhci \
  -audiodev pa,id=snd0 -device intel-hda -device hda-duplex,audiodev=snd0

To boot through UEFI instead of BIOS, add the OVMF firmware. The path depends on your distribution:

qemu-system-x86_64 -M q35 -bios /usr/share/ovmf/OVMF.fd  ...the rest as above...

What you'll see

A boot menu with a 5-second countdown. Just wait. The default entry, "squashfs root — Fasadas desktop", starts the desktop.
The desktop appears after a short while, with no login needed.

The other menu entries are there for when something goes wrong:

Entry	Use it when
squashfs root — Fasadas desktop	The normal desktop (the default).
squashfs root — Fasadas desktop, 1024x768	The picture looks wrong or is too big, especially in a VM.
squashfs root — verbose console	You want to see boot messages and get a text console.
initramfs root — verbose rescue console	The normal entries don't boot. A minimal system running from memory.
Install AnotherOS (console)	A text-mode installer, if the graphical one can't start.
12-inch MacBook 2017 — Fasadas desktop	You're on the 12" MacBook (2017). It turns on WiFi and the settings that machine needs.

Keep it between boots (optional)

The live system forgets everything when you shut down. To try the installer safely, give the VM an empty virtual disk and install onto that:

qemu-img create -f qcow2 aos-disk.qcow2 16G
qemu-system-x86_64 -enable-kvm -cpu host -m 4G -smp 2 \
  -cdrom k2225-u1559-anotheros-x86_64.iso -boot d \
  -drive file=aos-disk.qcow2,format=qcow2 \
  -nic user,model=e1000 -device qemu-xhci

Run AInstaller from Applications, pick the virtual disk and choose Erase disk and install. The only thing erased is the empty virtual disk. Afterwards, boot from the disk by dropping -cdrom ... -boot d.

QEMU has no real graphics chip, so GPU acceleration can't be tried in a VM. Everything else can.

Option 2: run it on a real computer from USB

Reminder: this erases the USB stick completely, and choosing the wrong drive erases that drive instead. Double-check the device name. Unplug other external disks if you're unsure.

Windows

Unzip the download.
Use Rufus (https://rufus.ie). Select the stick, select the ISO, and when Rufus asks, choose "Write in DD Image mode", not ISO mode. Or use balenaEtcher (https://etcher.balena.io), which writes the image as-is and can take the .zip directly.

macOS

diskutil list                         # find the USB stick, e.g. /dev/disk4
diskutil unmountDisk /dev/disk4
sudo dd if=k2225-u1559-anotheros-x86_64.iso of=/dev/rdisk4 bs=4m
diskutil eject /dev/disk4

Use the rdisk name (/dev/rdisk4), which is much faster. balenaEtcher works on macOS as well.

Linux

lsblk                                 # find the USB stick, e.g. /dev/sdX
sudo umount /dev/sdX?*                # unmount any mounted partitions of it
sudo dd if=k2225-u1559-anotheros-x86_64.iso of=/dev/sdX bs=4M \
        status=progress conv=fsync
sync

Write to the whole device (/dev/sdX), not a partition (/dev/sdX1).

Booting from the stick

PC: open the one-time boot menu at power-on (usually F12, F11, F8 or Esc, depending on the maker) and pick the USB stick. Turn off Secure Boot first on UEFI machines.
Intel Mac: hold Option (⌥) at the startup chime and pick the orange EFI Boot disk. On a MacBook with a single USB-C port you'll need an adapter, and it can't charge while the stick is plugged in, so start with a full battery.

The live system doesn't change your internal disk unless you run the installer.

Installing to disk (only if you really mean it)

AInstaller can erase a whole disk or install alongside macOS or Windows in free space. Before it writes anything it shows every partition and what will happen to it, and you have to confirm by typing the disk's name. It never resizes another system's partition. You make the free space yourself, using that system's own tools.

Even so: back up first. This is alpha software, and the installer is exactly the part that can lose you data.

The image doesn't run an SSH server unless you start it, and it contains no pre-authorised keys. The first time SSH is started, the machine creates its own unique host key. To turn it on for the current session, open a terminal and set a root password of your own first, then start the server:

echo 'root:choose-a-strong-password' | chpasswd
sh /etc/rc.d/sshd start

Known issues

It's alpha. Expect crashes, freezes, missing features and rough edges everywhere.
Live sessions don't keep changes. Settings and files are lost at shutdown. That's by design for a live image.
Hardware support is narrow. It's tested on a small set of lab machines: a Dell laptop, a 2011 MacBook Pro and a 2017 12" MacBook. Other computers may not boot, may lack WiFi, sound or graphics acceleration, or may behave oddly.
GPU acceleration applies to recent Intel graphics only. Web pages that run WebGL non-stop can still crash Firefox on those GPUs. Drawing the whole desktop on the GPU is present but switched off by default.
Very slow or failing disks can make the system sluggish while it writes. Improvements are in progress.
12" MacBook: Bluetooth and the webcam don't work.
2011 MacBook Pro: sleep (suspend) isn't available.
In a VM: no GPU acceleration (QEMU has no real graphics chip).

Reporting problems

Please include the kernel and userspace build numbers (k2225, u1559), your computer's make and model, and what you did before it went wrong. A photo of the screen is often the most useful thing you can send.

AnotherOS 0.9.0 (k2225 / u1559). Early preview, alpha. Use at your own risk.