9front

A fork of Plan 9, designed for distributed, networked computing.

AROS

Research Operating System is a lightweight, efficient, and flexible desktop operating system, designed to help you make the most of your computer. It's an independent, portable and free project, aiming at being compatible with AmigaOS at the API level

AlmeidaOS

x86-64 OS with its own bootloader, scheduler and limited libc all written from scratch

Animal

32 bit multithreaded operating system (formerly Gramado)

Asterinas

Linux-ABI-compatible kernel project written in Rust, based on what the authors call a "framekernel architecture"

AurixOS

A small multiplatform Operating System designed for developers and creators

AquilaOS

Operating System that is designed to be POSIX compliant and mostly ISA transparent

Arikoto

, GitHub - A Limine protocol, x86_64, C based personal Operating System development project that is inspired by and is aiming to have a similar nature to ToaruOS

BareMetal

, GitHub - 64 bit operating system written in Assembly for x86-64

Basekernel

A simple OS kernel for research, teaching, and fun

BoneOS

OS for everyone built by everyone

Bottlerocket OS

Linux-based OS meant for hosting containers.

Brutal

An operating system inspired by brutalist design that combines the ideals of UNIX from the 1970s with modern technology and engineering

cavOS

Amd64 operating system in C. Trying to make a full OS, with a simple and readable codebase

Charlotte

CharlotteOS kernel in Rust

ChibiOS

a complete development environment for embedded applications including RTOS, an HAL, peripheral drivers, support files and tools

Clive

A unikernel OS inspired by Plan9 and Nix developed at Universidad Rey Juan Carlos of Madrid

Cyjon

pure x64 assembly language operating system (related to Fern-Night project).

DragonOS

An x86-64 OS build from scratch.

Dreamos64

An x86-64 hobby os built from scratch

Embox

Configurable operating system kernel designed for resource constrained and embedded systems.

Equinox OS

A 32-bit x86 hobby operating system written from scratch in C++17 featuring a self-hosting C compiler, preemptive multitasking, demand paging, FAT32 read/write, a TCP/IP stack with HTTPS, and a built-in LVGL desktop.

Ethereal

Ethereal is an advanced modular operating system with support for networking and USB as well as a GUI-enabled userspace.

ExectOS

, GitHub - ExectOS is a modern, EFI-enabled, general purpose operating system written from scratch and implementing the XT architecture. It runs on x86 and x86_64 architectures and provides NT drivers compatibility layer.

Fern-Night

C language operating system (related to Cyjon project).

Fiwix

, GitHub - A UNIX-like kernel for the i386 architecture.

Fomos

Experimental OS, built with Rust.

FreeRTOS

, GitHub - IoT operating system for microcontrollers, by Amazon.

Genode

A FOSS operating system framework consisting of a microkernel abstraction layer and a collection of userspace components

Gloire

An OS built with the Ironclad kernel (a partially formally verified kernel with a small footprint for general-purpose and embedded OSes, written in SPARK and Ada) and GNU tools.

GreenteaOS

, Github - A free OS designed to be compatible with Windows executables

HalideOS

experimental operating system written entirely from scratch.

HarveyOS

A distributed operating system

HelenOS

multikernel multiserver OS

Hermit

A Rust-based, lightweight unikernel

House

Haskell User's Operating System and Environment.

Hubris

Hubris is an operating system for microcontrollers developed by Oxide Computer Company in Rust

Illumos

illumos is a Unix operating system which provides next-generation features for downstream distributions (like OmniOS, OpenIndiana, and Tribblix)

Interim

Minimalist OS with concepts from Lisp machines and Plan9

JSD-OS

A small operating system for 32 bit x86.

Jehanne

, GitHub - OS inspired by Plan9, 9front and Harvey OS

KiddieOS

UNIX-like 64-bit operating system written in Assembly, C++.

KnightOS

for z80 calculators

KolibriOS

MenuetOS fork

Lateralus OS

Bare-metal OS written in Lateralus with its own pipeline-native programming language, compiler, and VM

L4re

Operating system and hypervisor for security/safety-critical and virtualization-enabled applications.

LemonOS

, GitHub - UNIX-like 64-bit operating system written in C++.

Maestro

, Blog - Operating system written in Rust, aiming to be a lightweight version of Linux

Mako

Hobby OS for x86 from scratch, written in C

MaslOS

A 64 bit GUI multitasking Hobby OS written mostly from scratch in C++ and a bit of C/ASM.

MeetixOS

A hobby OS written in modern C++20 which aims to be Unix-like.

MentOS

An educational 32-bit linux-like Operating System.

MenuetOS

Hobby OS supporting 32 and 64 bit, written in Assembly language

Mimiker

, GitHub - Simple unix-like operating system for education and research purposes. MIPS microkernel.

Mimosa

, GitHub - Research Operating System that runs Scheme on bare-metal

Minoca OS

General purpose OS, written in C

MollenOS

MollenOS/Vali is a modern operating system that is built with focus on abstraction and a modular design, allowing anyone to port it to any architecture. It currently targets the x86-32 and x86-64 platform

myOS

Under development and Maintenance by a single Undergraduate who just wanted his machine to execute his own instructions.

MyXomycota

Monolithic kernel in C

NESOS

An OS for the Nintendo Entertainment System!

Nanos

Unikernel that is linux-compatible, written in C

NodeOS

OS using NodeJS and Linux

Northport

Monolithic kernel and support libraries for riscv64 and x86_64.

PathOS

Hobby OS based on MikeOS, written in Assembly Language

Pidi OS

Independent and minimalistic OS

PonyOS

, GitHub - ToaruOS-based, My Little Pony themed OS

PouplyOS

Simple OS for fun and learning, named after the ESISAR mascot Poulpy

PureDarwin

PureDarwin is a community project to extend Darwin into a complete, usable operating system

Qubes OS

Security-focused OS built on the Xen hypervisor, designed to isolate different compartments based on levels of trust.

RavynOS

A BSD-based OS project that aims to provide an experience like and some compatibility with macOS (formerly known as airyxOS)

Redox

written in Rust

rou2exOS

, Blog - A second iteration of the DOS-like hobby OS written in Rust and x86_64 assembly

Sanos

, GitHub - Sanos is a minimalistic 32-bit x86 operating system kernel for network server appliances running on standard PC hardware.

SayoriOS

Hobby OS for x86 computers, currently under active development, written in C

Sculpt OS

Genode based OS

Serenity

Graphical Unix-like operating system for x86 computers

SimpleOS

Simple Operating System coded in C and Assembly

Snowdrop OS

a homebrew operating system from scratch, in assembly language

Sortix

Hobby OS in C and C++ by Jonas 'Sortie' Termansen

Stanix

An open source modular hobby OS in C, with features such as dynamic linking and a page cache.

Syllable

Successor of AtheOS, Syllable is designed in the tradition of the Amiga and BeOS, but built using many parts from the GNU project and Linux.

SynestiaOS

32/64 bit operating system written in C for arm platform

TempleOS

Religious OS :-)

Theseus

A modern experimental OS written from scratch in Rust to explore novel OS structure and state management techniques.

Thor

64bit operating system mostly written in C++

ToaruOS

Hobby operating system from scratch

Týndur

Hobby operating system build by the Lowlevel community. Written in C and Pascal

Ultron OS

x86 Operating System written in C++, High School Project

Unikraft

A modular unikernel for specialization, high efficiency, performance, and security; Linux/POSIX-compatible; mostly in C

Vinix

Vinix is an effort to write a modern, fast, and useful operating system in the V programming language

Visopsys

Open Source Hobby OS developed since 1997

Windows 95 in Electron

Hobby Windows 95 implementation in Electron

Xv6

A teaching operating system developed in the summer of 2006 for MIT's operating systems course

ZealOS

The Zeal Operating System is a modernized, professional fork of the 64-bit Temple Operating System, TempleOS.

ackOS

A simple 64-bit operating system.

aurora_os

Written in Rust.

dahliaOS

dahliaOS is a modern, secure, lightweight and responsive operating system, combining the best of GNU/Linux and Fuchsia OS.

duckOS

A hobby UNIX-like OS with a graphical window manager for x86 computers.

eggos

A Go unikernel running on x86 bare metal

emerald

An operating system kernel written for fun in C

gopher-os

A proof of concept OS kernel written in Go

hhuOS

hhuOS is a small operating system written in C++ and Assembler for the x86-architecture. The main purpose of this project is to show how different aspects of operating systems theory can be implemented and linked together. The system is not aimed to be a full-featured operating system for daily use.

hydrogen

toy OS. 64-bit, preemptive multitasking kernel supporting EFI, PCIe, SATA, framebuffer graphics mode, HFS+.

lyre

x86 kernel and distribution powered by mlibc, GNU userland tools, and other common *nix software.

managarm

Pragmatic microkernel-based OS with fully asynchronous I/O

menix

A minimal and expandable Unix-like operating system.

moros

MOROS is a hobby operating system written in Rust for the x86 architecture.

mOS

A hobby operating system developed from scratch

nopeos

Simple OS kernel with BASIC interpreter for x86

octox

Unix-like OS in Rust inspired by xv6-riscv

oneOS

x86-32 and ARMv7 kernel with pre-emptive multi-threading, window manager and editor

opuntiaOS

an operating system targeting x86, ARMv7, Aarch64.

orange_slice

A research kernel and hypervisor attempting to get fully deterministic emulation with minimum performance cost. In Rust

Ovation

A simple, hobby, 64-bit operating system that focuses on simplicity, portability and maintainability. Written in C.

pranaOS

A unix operating system written from scratch in c / c++

r3

A hobby x86_64 Operating System kernel written in Rust -- with minimal functionalities

skiftOS

, GitHub - A simple, handmade, operating system with a graphical user interface.

soso

Simple unix-like operating system written in Nasm assembly and mostly in C

tilck

A Tiny Linux-Compatible Kernel.

tock

, GitHub - A secure embedded operating system for microcontrollers

unox-os

Unox is an educational unix-like operating system

willOS

A minimal 64 bits kernel (Operating System that cannot "operate" a lot of things)

Darwin XNU

The XNU kernel source code for use in MacOS and iOS

FreeBSD

, Github - Unix-like operating system based on the BSD

FreeDOS

DOS compatible OS

Haiku

BeOS inspired OS

Linux

Linux kernel

Minix

, Github - Unix-like operating system based on a microkernel architecture

MS-DOS

The original sources of MS-DOS 1.25 and 2.0

NetBSD

, Github - Unix-like operating system based on the BSD

OpenBSD

, Github - Unix-like operating system based on the BSD

Plan 9 from Bell Labs

An OS from the creators of Unix, extending the Unix philosophy of "everything is a file" with a network-centric file system, namespaces and distributed computing.

ReactOS

, Github - A free Windows-compatible Operating System

SystemV

AT&T UNIX System V Source Code

How to Make a Computer Operating System

in C++

Intermezzos

A follow along book to build IntermezzosOS in Rust

Linux Kernel in a Nutshell

Covers the entire range of kernel tasks, available as chapters or one PDF

The little book about OS development

by Erik Helin and Adam Renberg

Think OS

A Brief Introduction to Operating Systems by Allen B. Downey

Operating System Development Series

OS from the ground up in C

Operating Systems: Three Easy Pieces

Easy to read book covering virtualization, concurrency and persistence

xv6: a simple, Unix-like teaching operating system

Book for Xv6

Operating Systems: From 0 to 1

Bootstrap yourself to write an OS from scratch by Do Hoang Tu

Osdev Notes

How to write an operating system from scratch by Ivan G. and Dean T.

lytlnyblOS

A beginner-friendly guide to building a 32-bit x86 operating system from scratch.

Baking Pi – Operating Systems Development

by University of Cambridge

Build a minimal multi-tasking OS kernel for ARM from scratch

by Jim Huang

Bran's Kernel Development

by Brandon Friesen

How to write a Linux kernel patch and submit it

by Greg Kroah-Hartman

Presentation on how the Linux kernel is developed

by Greg Kroah-Hartman

os-tutorial - How to create an OS from scratch

by Carlos Fenollosa

Roll your own toy UNIX-clone OS

by James Molloy

Writing an OS in Rust

by Philipp Oppermann

Making a RISC-V Operating System using Rust

by Stephen Marz

Operating systems development for Dummies

by Leo Whitehead

Kernels 101 – Let’s write a Kernel

by Arjun Sreedharan

Kernels 201 - Let’s write a Kernel with keyboard and screen support

by Arjun Sreedharan

Writing a Tiny x86 Bootloader

by Joe Bergeron

Writing a Bootloader

by Alex Parker

Learning operating system development using Linux kernel and Raspberry Pi

Learning operating system development using Linux kernel and Raspberry Pi

mya

a fun project to create OS from scratch by Erfan

AMUNIX : Custom Unix Shell Guide

by CryogenicBoom, a simple SHELL development documentation.

Genodians

Stories around the Genode Operating System

os-dev

Wiki with everything you need to know

Lowlevel

A wiki about creating an OS from scratch. In German

POSIX

Standards for maintaining compatibility between operating systems

Rust OSDev

Newsletter about OS development in Rust

OSRTOS

List of open source real-time operating systems

Multicians

The Multicians web site presents the story of the Multics operating system for people interested in the system's history

The benefits and costs of writing a POSIX kernel in a high-level language

by Cody Cutler, M. Frans Kaashoek, and Robert T. Morris, MIT CSAIL

Mimosa

, GitHub - Research Operating System that runs Scheme on bare-metal

Unikraft: Fast, Specialized Unikernels the Easy Way

by Kuenzer et al., EuroSys 2021

Write your own Operating System

[video]

Nanobyte

Kernel dev from scratch by Dragon Zap Education

OSDev Lecture Series by AptRock327

A Beginner’s Guide to Linux Kernel Development (LFD103)

The Linux Kernel Module Programming Guide

by Peter Jay Salzman, Michael Burian, Ori Pomerantz, Bob Mottram, Jim Huang

The Linux Kernel documentation

Working with the kernel development community

Linux Kernel Teaching

linux-insides

by Alex Kuleshov

Linux Kernel Workbook

bootlins interactive Linux kernel map

Linux kernel system call table for all archs

by Marcin Juszkiewicz

OldLinux

A Heavily Commented Linux kernel source and more

sam4ks Linux Kernel Resources

xairys Linux Kernel Exploitation

A bunch of links related to Linux kernel fuzzing and exploitation

fibdrv Linux kernel module that calculates Fibonacci numbers

kernel-security-learning

syzbot

bugs

syzkaller

kernel fuzzer

Doing more with lore and b4

, slides

Der Linux Kernel Entwicklungs-Workflow

(2023, German) by Rouven Czerwinski

How to write Rust in the kernel

by Daroc Alden

b4

, docu, a tool to help with email-based patch workflows

clang-extract

a tool to extract code content from source files using the clang and LLVM infrastructure.

hackermail

a mails management tool for hackers who collaborate using mailing lists

kworkflow

reduce the overhead with infrastructure setup for Linux development

virtme-ng

quickly build and run kernels inside a virtualized snapshot of your live system

Planet Kernel

Become a Linux kernel contributor - Part 1

by Javier Carrasco

Become a Linux kernel contributor - Part 2

by Javier Carrasco

Become a Linux kernel contributor - Part 3

by Javier Carrasco

Fixing bugs in the Linux kernel with Syzbot, Qemu and GDB

by Javier Carrasco

b4 for Linux kernel contributors

by Javier Carrasco

Use b4 for kernel contributions

by Marcus Folkesson

Using lei, b4, and mutt to do kernel development

by Josef Bacik

netdev in 2023

by Jakub Kicinski

Five commands to crash the kernel

by Marcos Paulo de Souza

You can be a kernel hacker!

by Julia Evans

4 paths to being a kernel hacker

by Julia Evans

Guessing Linux kernel registers

by Julia Evans

How I got robbed of my first kernel contribution

by Ariel Miculas

Apply Linux Kernel Patches from LKML

by Adam Young (before he got aware of b4)

My patch review workflow

by Josef Bacik

Linux Kernel Develop Workflow

by Tommaso Merciai

Apply a Linux kernel patch to the stable tree

(2009) by Greg Kroah-Hartman

Patch Workflow With Mutt 2019

by Greg Kroah-Hartman

Debug kernel with KGDB

by Marcus Folkesson

Linux Kernel Debugging

How I Learned to Love the Email Patch Developer Workflow

by Emily Shaffer

Bug hunting

Bisecting a bug

Who Made That Change and When: Using Cregit for Debugging

by Shuah Khan

Make stack dump output useful again

Debugging Analysis of Kernel panics and Kernel oopses using System Map

by Sanjeev Sharma

Understanding a Kernel Oops!

by Surya Prabhakar

Tracing Linux kernel with retsnoop

by Andrii Nakryiko.

The advantages of an email-driven git workflow

by Drew DeVault

Code review at the speed of email

by Drew DeVault

Linux Plumbers

, YT

The Linux Foundation