Ethereal

A custom all-in-one operating system, written for speed, memory conservation, and reliability.\ Formerly known as reduceOS

What is Ethereal?

Ethereal is a project with the goal of creating a fully functional OS from scratch with all components a modern OS would have.

Currently, the project is developing its usermode stages.

Screenshots

\ Modern, 1080p desktop environment

\ Ethereal older main desktop environment with DOOM

\ Ethereal booting in debug mode

\ Ethereal on Libera chat (#ethereal)

\ Ethereal running DOOM

\ Ethereal running a neofetch clone made for it (whatarewe)

Features

• Full SMP-enabled kernel
• Custom window manager (Celestial)
• USB support for UHCI/EHCI/xHCI controllers
• AHCI/IDE support
• Networking stack with E1000 and RTL8139 network card driver
• Priority-based round-robin scheduler with a well-tested API
• Support for the mlibc C library and its wide variety of functions
• Full ACPI support with the ACPICA library (with backup MinACPI library that doesn't have AML parsing)

Project structure

• base: Contains the base filesystem. Files in base/initrd go in the initial ramdisk (for non LiveCD boots) and files in base/sysroot go in sysroot.
• buildscripts: Contains buildscripts for the build system
• conf: Contains misc. configuration files, such as architecture files, GRUB configs, extra boot files, etc.
• drivers: Drivers for Hexahedron, copied based on their configuration.
• external: Contains external projects, such as ACPICA. See External Components.
• hexahedron: The main kernel project
• libkstructures: Contains misc. kernel structures, like lists/hashmaps/parsers/whatever
• libc: Contains mlibc

Building

ACPICA notice

If you use ACPICA (it is on by default), you must download the tarfile from here and extract it to external/acpica/acpica-src

Else, you can edit conf/build/.mk and set USE_ACPICA to 0.

Building

To build Ethereal, you will need an Ethereal toolchain for your target architecture.\ The Ethereal toolchain can be found at the repository

Other packages required: grub-common, xorriso, qemu-system, meson, ninja

Edit buildscripts/build-arch.sh to change the target build architecture. \ Running make all will build an ISO in build-output/ethereal.iso

Currently, Ethereal's lack of filesystem drivers means that LiveCD boots are usually the best option.\ The initial ramdisk in a LiveCD is the sysroot, and if the OS detects the boot it will copy the initial ramdisk into RAM.

Kernel arguments

A lot of times, Ethereal fails to load. This is expected. Please start a GitHub issue.

You can solve some problems by using 'e' to open a GRUB configuration and adding some kernel arguments to the end of the multiboot entry.\ Here is a small list:

• --debug=: Options are console and none. If console, will redirect kernel debug output to the screen. Useful for debugging
• --noload=: Comma-separated list of driver (.sys) files to not load. Problematic drivers: usb_xhci.sys, ahci.sys, ps2.sys (if you don't support PS/2),
• --no-acpica: Disable the ACPICA library and fallback to MinACPI implementation. Only useful in extreme cases.
• --no-acpi: Disable all ACPI implementations. Disables SMP as well.
• --disable-smp: Enable ACPI, but disable SMP
• --disable-cow: Disable copy-on-write. Not recommended, but can be useful in extreme cases.
• --no-psf-font: Don't load the PSF font from initrd

External components

Certain external components are available in external, libc, and other parts of the kernel. Here is a list of them and their versions:

• ACPICA UNIX* (Intel License): Version 20240927 available here
• libmusl math library (MIT License): available here
• freetype (GPL license): available here
• mlibc (MIT license): Ethereal fork available here
• tinf (zlib license): available here
• json-parser (BSD 2-clause license): available here
• PlutoSVG (MIT license): available here

Credits

A lot of Ethereal's design was inspired by ToaruOS by klange - thank you!

Ethereal's virtual memory manager design and other parts was inspired by Astral by @mathewnd

Some code from Astral was also used, credited where appropriate. A license file is included in external/.

The Ethereal logo and Mercury theme were designed by the artist ArtsySquid

Licensing

Hexahedron and all other non-external components of Ethereal fall under the terms of the BSD 3-clause license (available in LICENSE).\ All files, unless specified in the copyright header, fall under this license. Any file without a copyright header is NOT protected by BSD 3-clause.

LICENSING ISSUES: If a file is found without proper commenting, immediately contact me (preferably through a public channel such as GitHub issues for transparency) directly to resolve it.

Ethereal's goal has NEVER been to take code, but it has happened in the past. Please contact me! --- Tranlated By Open Ai Tx | Last indexed: 2026-05-23 ---