Open Source Mac Operating System Kernels

We love macOS, but we’re not a fan of the ever-closing hardware and ecosystem. So we are creating ravynOS, an OS aimed to provide the finesse of macOS with the freedom of FreeBSD. This is a developer preview image that’s mainly intended for helping build the system. We recommend running in a virtual machine, although it should work on any hardware supported by FreeBSD-CURRENT (14.0) with at least 2GB (8GB recommended) RAM. PLEASE NOTE: On 2022-02-14, we decided to abandon the current path of using X11/KDE desktop components and write from scratch a new UI that will align better with our goals. This stepping back will slow the project but ultimately should result in a better outcome. We intend to bring many of the features you’ve come to love from macOS to ravynOS like clean design, global menus, and drag-and-drop installs. All of your FreeBSD ports and apps, Linux apps, and even trivial Darwin & macOS binaries can now run on ravynOS. And we’re actively working on improving it!

C-BIOS is an open source BIOS for MSX computers. C-BIOS can be shipped with MSX emulators so they are usable out-of-the-box. This project aims to improve C-BIOS by fixing incompatibilities with the MSX BIOS and the development of a Disk ROM.

This project reimplements from scratch the RPL language made popular by HP programmable calculators, in portable C/C++. The main goal is to release a complete computing environment for various targets. There's currently 4 active targets: the HP 50g, HP39gs and HP40gs calculators and a PC simulator (see the downloads section!). Other ports are planned for the future.

This is a small library that allows comunicating with a Webasto (tm) W-Bus capable car heating system. Runs on Personal Computers or for embedded devices (slim design). Easily portable. Includes a Heater manager, heater controller program and more. The GIT repository (CVS is deprecated) also includes a control unit application to control W-Bus capable devices, a W-Bus compatible heater unit firmware application and a heater simulator for testing purposes. Also, a serial port loop back driver for linux is included to simulate OBD II K-Line adapters.

Nuttx is a real time embedded operating system (RTOS). Its goals are: (1) small footprint usable in deeply embedded, resource constrained environments, (2) fully scalable from tiny (8-bit) to moderate (32-bit), (3) standards compliance, (4) real time, and (5) totally open. Think "Tiny Linux". NuttX is now and Apache project in incubation. See https://nuttx.apache.org/download/ for the latest downloads.

TinyOS is an operating system for embedded sensors and networks. Versions 2.0 and later of TinyOS should be downloaded from www.tinyos.net.

The Darwin Source repository is intended to fill a void left by the closure of the OpenDarwin project: providing a permanent and public repository for the open source components of Mac OS X.

MinopsOS is a tiny operating system for PC computers. It's small enough to fit inside the boot sector of a floppy disk.

HelenOS is a portable microkernel-based multiserver operating system written from scratch. It decomposes key operating system functionality such as file systems, networking, device drivers and graphical user interface into a collection of fine-grained user space components that interact with each other via message passing. A failure or crash of one component does not directly harm others. HelenOS is therefore flexible, modular, extensible, fault tolerant and easy to understand. HelenOS does not aim to be a clone of any existing operating system and trades compatibility with legacy APIs for cleaner design. Most of HelenOS components have been made to order specifically for HelenOS so that its essential parts can stay free of adaptation layers, glue code, franken-components and the maintenance burden incurred by them.

Unix-like operating system for the TI-89 and TI-92+ graphing calculators.

The aim of our project is to create a portable microkernel and a set of OS services that allow good local performance, multiple concurrent operative system personalities (ie UNIX and a native interface) and easy integration of distributed components.

Provide secure and stable OS, based on highly modified Linux Kernel, own package system, like "BSD Ports". Compatible with x86, Power PC. Easy to use of any level users. Complete Documentantion in many languages. 99% compatible with Windows.

This project has been moved to http://pros.cs.purdue.edu/ PROS is a lightweight and fast alternative operating system for the VEX Cortex Microcontroller. It features multitasking, low-level control, and Wiring compatible functions to harness the full power of the Cortex. With a real-time kernel based on FreeRTOS and a development environment built on Eclipse CDT, PROS uses proven software to increase the reliability and usability of the VEX development system across all three major computing platforms. PROS is currently under active development to make it usable for VEX high school and middle school teams. PROS is intended for advanced VEX users seeking to move beyond competing environments. Eclipse and FreeRTOS have their own licensing agreements. Please see http://www.eclipse.org/legal/epl-v10.html and http://www.freertos.org/a00114.html for details.

An implementation of the Ext2 (Linux) filesystem for Mac OS X.

MikeOS is a an open source 16-bit operating system for x86 PCs, written in assembly language, which boots from a floppy disk or CD-ROM. It is designed as a learning tool for x86 assembler and basic OS design.

Venom Operating System. A protected mode kernel for i386+ PC's. Designed for games and multimedia.

This is a java implement FUSE binding (FileSystem in User Space), again, this can be used as remote file system by io package in this project.

16 bit Forth for PC. No OS required.

The Trion Object Oriented Operating system is an OS that is designed to meet the needs for the 21st century, with a kernel written in C++ and modelled in UML, and lots of features. The project is run by a team of OSDev.org community members.

Implementation of virtual threads for the XS-1. Currently a simple context switching implementation for the XMOS XS-1 architecture (Gn, Ln products). Allows a user to run low speed processes on a single thread using time sliced scheduling.

XNU Kernel Extras contains drivers designed to extend the functionality provided by the default Mac OS X kernel and drivers.

A Trivial Operating System for 8051 (ATOS51). ATOS51 is a trivial operating system for 8051 microcontroller. As its name, it provides only multitasking feature.

AWOS: The Universal Operating System.

Akalon is a Bare-Bones Embedded RTOS that's designed to be simple and portable to any Microprocessor or System (Board). Currently supports the Intel and ARM Architectures.

Soft-realtime operating system, based in a microkernel design and providing QoS and persistence capabilities.