Mizu

Kernel MX 27

Its own kernel.
On every core.

MX 27 boots on real UEFI PCs and puts every processor to work. Programs run in their own address spaces, a mistake in one stops that one alone, and the desktop keeps drawing while a disk works.

x86-64UEFI, from USB stick or disk

SMPall processors, one scheduler

Ring 3every program in its own space

A / Btwo system slots, updates that roll back

KFS

A file system
that keeps its word.

KFS journals every change, so a power cut leaves the disk whole. Changes gather in memory and reach the disk together, small files are made in a fraction of a millisecond, and SSDs are told which space is free.

Journal: no checks after a power cut
Write-back with a two-second promise
Page cache: programs start from memory
TRIM for SSDs, minding the few that mishandle it

2 500 power cuts in the middle of writing, on purpose, in our tests. 0 damaged volumes after them.

Speed

Fast.
And faster every week.

The same 2011 laptop, the same SATA SSD. Only Mizu changed.

Claude Code starts

before

3.5 s

now

0.19 s

Look up a file (stat)

before

95 µs

now

8 µs

Open and close a file

before

110 µs

now

14 µs

Make a small file

before

5.8 ms

now

0.6 ms

Desktop

Feels like home
from the first click.

Windows you drag and resize, a launcher that knows every program, a dock, notifications and screenshots. The Kasumi look is calm and clear, in light and in dark.

The Mizu desktop: top bar, dock and launcher

NetSurf, the web browser — NetSurf, the browser

Kawa

Linux programs,
as they were built.

Kawa, the Mizu Subsystem for Linux, runs Linux programs without changing them. Turn it on in Programs and Features, bring in Alpine Linux with one command and install what you need with apk: bash, git, tmux, compilers, even Claude Code.

kawa --install alpine
kawa apk add bash tmux git
kawa bash

Apps

Everything for
a day at the computer.

A web browser, a music and video player, a Telegram client, a paint program, a calculator, card games and more. The App Store brings the rest, signed and checked before anything is unpacked.

Setup

From stick to desktop
in minutes.

1
Write the stick
Download the image and write it with Rufus (DD mode) or balenaEtcher.
2
Start from it
Pick the stick in your PC's boot menu. Secure Boot off.
3
Try or install
Try it from the stick, or install it: the whole disk, or the free space beside Windows or Linux. Mizu puts itself in the boot menu.
4
Four questions
On the first start from the disk: you, sign-in, region, a look. Then it is yours.

Welcome to Mizu: the four questions on the first start

In detail.

Kernel

MX 27, x86-64, multiprocessor, written in C. Grew out of Koi-DOS and has since been largely rewritten.

Starts on

64-bit UEFI PCs, from a 2011 laptop to today's, from a USB stick or an internal SATA or NVMe disk.

File systems

KFS with a journal; FAT32 for sticks and the EFI partition; SquashFS for the system image.

Updates

Signed, in two slots: a new system that does not start falls back by itself. Stable, Preview and Alpha channels.

Accounts

Administrators and standard users, PINs or passwords, file permissions, a prompt before system changes.

Languages

English, Ukrainian, Russian, Polish, Czech and Greek, with more on the way.

Linux

Kawa runs unmodified x86-64 Linux programs: musl and glibc, threads, sockets, terminals, tmux.

Licence

Mizu itself is MIT: free, with the source open to read, build and change. Third-party programs and parts keep their own licences (NetSurf, DOOM, Quake, Heretic and DOSBox are GPL): see the list.

Mizu.

Built from the ground up.
The kernel, the file system, the desktop, the apps: all its own.

Its own kernel.
On every core.

A file system
that keeps its word.