Download

Put it on a stick

SchOS ships as one bootable ISO. It boots on UEFI, runs entirely from RAM, and touches nothing on the machine unless you tell it to — there is no installer yet, and that is the point of trying it this way.

Download the ISO Build it yourself

schos.iso · about 62 MB · UEFI x86-64 · nothing is written to your disks

Before you do

This has booted on exactly one real machine

Everything below QEMU is honest reporting rather than a compatibility list. SchOS drives real hardware, and it has been run on a very small number of it.
QEMU / OVMF boots
Asus Chromebox Guado CN62 under test
Anything else unknown

If it does not boot, the kernel log is on the screen from its first line — that is deliberate, and it is there because of this machine. A photo of where it stops is a genuinely useful bug report.

Writing it

Two ways onto a stick

Ventoy first, because it is the one that does not cost you the stick. An ISO copied onto a Ventoy drive sits next to every other ISO on it, and the drive stays an ordinary drive.

Ventoy

recommended
Copy the file. That is the whole procedure — Ventoy finds it and offers it in its menu at boot, and the stick remains usable for everything else. 
$ cp schos.iso /run/media/you/Ventoy/

This is how SchOS is actually tested on hardware. No optical drive has been involved at any point.

dd

destructive
Writes the image over the whole device. Check the device name twice — there is no confirmation and no undo, and the wrong letter takes a disk with it. 
$ lsblk
$ sudo dd if=schos.iso of=/dev/sdX \
       bs=4M status=progress conv=fsync

of= is the whole device, not a partition — sdX and never sdX1.

First boot

What actually happens

Written out because a system you have never seen before gives you no way to tell "working" from "stuck", and the difference is worth knowing in advance.

  1. 1
    Step one

    The loader

    A splash, and F8 for boot options — including the resolution the whole machine will come up in. It is a PE/COFF loader built with clang and lld-link; there is no BIOS path, so the firmware has to be in UEFI mode.

  2. 2
    Step two

    The kernel log

    On screen, from the first line that can draw. Cores, the PCI bus, the network card, the filesystem. If it stops, it stops somewhere you can read.

  3. 3
    Step three

    A shell

    schinit starts one on the console and a second on tty2. mksh is /bin/sh, with zsh beside it and the real toybox userland behind both.

  4. 4
    Step four

    Twelve terminals

    Ctrl+Alt+F1…F12 switches between them — the one chord a Linux host does not take for itself — or chvt N from a shell.

Nothing is written to your disks and nothing persists. The root filesystem is in RAM; the machine is exactly as you left it after a reboot, including the parts of it you were hoping to keep. There is no installer — 1.0 is where that starts.

Or build it

Clone it, build it, boot it

The toolchain is one file. On NixOS shell.nix brings the whole thing in; elsewhere it is clang, lld, GNU make and a host compiler — see the build guide. 

$ git clone <the repository> schos && cd schos
$ nix-shell            # NixOS only; elsewhere see the build guide
$ make iso             # produces schos.iso
$ make qemu            # or just run it, without a stick

make qemu is the one to reach for first. Everything on this page works there, it takes seconds rather than a reboot, and a serial console beats a photograph of a screen.