Open-source alternatives to Apple Oss Distributions Xnu

WinFSP is a framework for implementing custom file systems on Windows. It enables the creation of user-mode file systems that appear as standard disk drives or network shares to the operating system, allowing developers to implement file system logic in user space via a proxy architecture that avoids the need for custom kernel code. A primary differentiator is its FUSE compatibility layer, which maps POSIX-based file system calls to native Windows requests. This allows existing file systems written for the FUSE API to be ported to Windows and Cygwin environments. The project covers a wide ra

Limine is a multiprotocol operating system bootloader that bridges low-level hardware initialization and system software across legacy BIOS and modern UEFI firmware environments. It executes directly on bare-metal hardware without an underlying operating system kernel or standard C library, parsing storage media and filesystems during the early boot sequence before OS drivers load. The software targets diverse processor architectures including x86, ARM, RISC-V, and LoongArch through discrete target binaries built from shared source code. It reads files directly from FAT and ISO9660 storage f

TencentOS-tiny is a real-time operating system for microcontrollers designed to manage task scheduling and resource allocation across various hardware modules. It functions as an embedded platform and modular kernel for deploying real-time software on different chip architectures. The system includes built-in protocol stacks to enable secure data transmission and connectivity between terminal IoT devices and cloud platforms. The project covers real-time task management, embedded software deployment, and microcontroller administration. It utilizes a modular microkernel architecture and a har

This repository contains the complete source code for the OpenBSD operating system and its base utilities. It is a Unix-like operating system focused on a secure, portable, and multi-user environment, featuring a C-based system kernel that manages hardware resources and provides essential services. The project provides a source-based system construction model to compile the core kernel and base utilities from raw files. It includes a cross-compilation toolchain for generating the tools and headers necessary to build binaries for target architectures different from the host machine. The codeb

Kernel is an educational hobby operating system and low-level systems programming project written in Rust. Designed for students and hobbyists, the project provides a minimalist environment to explore computer architecture, CPU design, and kernel development directly on hardware without relying on a standard library or underlying operating system. The implementation features a freestanding language runtime and a custom target specification that replaces standard library components for bare-metal execution. It includes a multiboot bootloader interface to parse early-boot hardware handoff stat

The Linux kernel source tree is core system software tailored specifically for Rockchip processor architectures and embedded hardware boards. It manages hardware resources, processor execution contexts, memory allocation, and process scheduling for custom computing platforms. The project provides low-level hardware abstraction, initialization routines, and a collection of kernel modules designed to control integrated silicon components, storage, and networking hardware. The codebase incorporates hierarchical data structures to describe physical board layouts, memory maps, and peripheral conne

This repository provides the Android device kernel and the corresponding Linux kernel source tree. It serves as the foundational codebase for managing the hardware architecture and power management of mobile devices. The project includes a comprehensive mobile hardware driver set designed to manage device-specific components, such as CPUs, GPUs, and cellular modems. The source code supports activities including Android kernel customization, custom ROM development, Linux kernel auditing, and mobile driver development.

This project provides a structured educational curriculum designed to teach Linux kernel internals and system architecture. It serves as a comprehensive training resource for developers, offering hands-on laboratory exercises that cover core operating system principles such as memory management, process scheduling, and interrupt handling. The curriculum distinguishes itself by mapping theoretical concepts directly to kernel source code, allowing learners to navigate and analyze system internals through practical implementation tasks. It facilitates the development of hardware device drivers a

rCore is a Rust-based operating system kernel and microkernel designed for Linux compatibility. It functions as a self-hosted development kit that implements a system call interface to support the execution of standard Linux userspace applications. The system is designed for modularity, featuring a mechanism for loading and integrating kernel modules into the active environment without requiring a system reboot. The kernel provides core operating system capabilities, including virtual memory mapping for process isolation, a disk-based file system for data persistence, and a layered network p

Aircrack-ng is a wireless security auditing suite used for monitoring, attacking, testing, and cracking wireless network encryption keys and passwords. It functions as an 802.11 packet analysis tool, a wireless frame injection tool, and a network mapper to identify vulnerabilities and active clients within a wireless environment. The suite includes a dedicated WPA/WPA2 password cracker that recovers network keys by analyzing captured handshakes through dictionary and brute-force attacks. It enables the construction and transmission of fabricated 802.11 packets to trigger specific network resp

This project is a Linux kernel designed for Windows Linux integration, providing the underlying operating system kernel required to execute binary files and applications within the Windows Subsystem for Linux. It utilizes hypervisor-based virtualization to run a full kernel within a lightweight utility virtual machine managed by a Windows host. The repository enables the customization and compilation of the kernel from source. This allows for the modification of system behavior, the addition of specific drivers, and the tailoring of hardware compatibility for virtualized environments. The sy

rkt is a pod-native container engine and runtime for Linux that executes containerized applications as isolated pods. It serves as an OCI container runtime and a Linux container manager, supporting the execution of images based on Open Container Initiative, appc, and Docker specifications. The project distinguishes itself by offering hardware-level container isolation, allowing pods to run within virtual machines using KVM or QEMU for a dedicated kernel. It further separates itself through secure container deployment practices, utilizing SELinux mandatory access control and TPM-backed integri

NuttX is a POSIX-compliant real-time operating system designed for microcontrollers ranging from 8-bit to 64-bit architectures. It provides a deterministic execution environment with a real-time task scheduler and a POSIX embedded kernel to ensure portable code execution across diverse hardware targets. The project distinguishes itself through a comprehensive hardware abstraction layer that provides standardized drivers for I2C, SPI, CAN, and USB across various semiconductor chipsets. It also features an embedded networking stack supporting TCP, UDP, IPv4, and IPv6, alongside industrial proto

ReactOS is an open-source operating system designed to be binary compatible with Windows applications and drivers. It consists of a low-level system kernel that manages hardware resources and a binary compatibility layer that enables the execution of software designed for the Windows binary interface. The project implements a cross-platform build system and toolchain for compiling and deploying bootable operating system images across different hardware architectures. This includes the use of cross-compilation toolchains and a hardware-abstraction layer to support various processor and motherb

v4l2loopback is a Linux kernel video driver that creates virtual video devices to route video streams between applications. It functions as a software-defined video source, simulating physical hardware to provide a standard video input for applications that require a capture device. The project enables video stream routing by piping data from one process to another using the Video4Linux2 standard. It includes mechanisms for device capability masking and conditional reporting to bypass strict hardware detection requirements in external software. The driver provides tools for virtual camera si

KernelSU is a kernel-based root management framework for Android that provides administrative access to applications by operating directly within the operating system kernel. By integrating management logic into the kernel source, it enables system-wide permission control through syscall interception and function patching. This approach allows for the enforcement of fine-grained mandatory access control, assigning custom security domains to root processes to restrict their capabilities and prevent unauthorized actions. The project distinguishes itself through a systemless modification archite

The Linux kernel is a monolithic operating system core that manages hardware resources, memory, and process scheduling across diverse computing architectures. It provides a standardized, POSIX-compliant environment for application execution while maintaining a modular driver framework that allows for the dynamic loading and removal of hardware interfaces. The project is distinguished by its high-performance concurrency toolkit, which utilizes lockless synchronization primitives and read-copy-update mechanisms to manage shared data access in multi-core environments. It incorporates a comprehen

G-helper is a system utility designed for the management and optimization of ASUS laptop hardware. It functions as a background service that interfaces directly with kernel-level drivers and ACPI tables to provide granular control over device performance, thermal profiles, and power states. The utility distinguishes itself by offering automated firmware orchestration, which handles the retrieval and verification of manufacturer-signed updates to maintain system stability. It also provides specialized hardware control, including the ability to toggle between integrated and dedicated graphics m

Arpl is a bootloader manager and custom kernel loader for network attached storage devices. It provides a network boot environment to automate the fetching, flashing, and installation of modified operating systems and kernels onto hardware storage. The project distinguishes itself through a remote management suite that exposes bootloader controls via a web browser, secure shell connection, or local terminal. It utilizes RSS feeds to automate the retrieval of the latest system images and version metadata for online updates. The system handles hardware boot configuration by mapping network int

Bottlerocket is a container-optimized operating system and minimal Linux distribution designed specifically for hosting container workloads. It functions as an immutable infrastructure OS, utilizing a read-only root filesystem and atomic partition swapping to ensure consistent and reversible system updates. The system is distinguished by an API-driven host manager that replaces traditional shell-based configuration with a local REST API for administrative tasks. To maintain security and stability, it employs a dual-runtime isolation model that separates workload runtimes from system operation

MPX is a cross-platform framework designed to build applications for multiple mini-program ecosystems and the web from a single codebase. It utilizes a static transpilation pipeline to transform source code into platform-specific bundles, employing a single-file component system that encapsulates templates, logic, and styles. The framework provides a reactive state management system that automatically synchronizes application data with the user interface through computed properties and watchers. The project distinguishes itself through a robust build-time toolchain that supports sub-package p

Kata Containers is an OCI container runtime that launches containers inside lightweight virtual machines to combine hardware-level isolation with container operational speed. It functions as a hardware-isolated container engine and lightweight VM hypervisor, providing a virtual machine monitor interface that abstracts multiple hypervisors to optimize for performance or specific hardware emulation. The project distinguishes itself through a confidential computing runtime that leverages hardware-backed trusted execution environments, such as Intel TDX and AMD SEV-SNP, to protect data in use. It

ipsw is a specialized toolkit for iOS firmware analysis, binary reverse engineering, and hardware interaction. It provides a suite of tools for downloading, extracting, and analyzing firmware images and kernel caches, alongside a MachO binary analysis tool for disassembling and patching executables. The project distinguishes itself through integrated language-model-powered code reconstruction to translate machine code into high-level source code. It also features an automation client for the App Store Connect API to manage certificates and application settings. The framework covers a broad r

This project is a collection of minimal operating systems, bootloaders, and hardware drivers used to demonstrate low-level x86 system programming and hardware interfacing. It serves as a kernel development toolkit and a system programming lab designed for testing architecture concepts and hardware behavior within a system emulator. The repository provides reference implementations for creating bootable disk images and loading kernel stages. It includes guides for implementing protected mode transitions, memory paging, interrupt descriptor tables, and symmetric multiprocessing on x86 hardware.

This project provides a Linux kernel development environment and a system emulation suite for building and debugging kernel modules and baremetal assembly across multiple hardware architectures. It functions as a comprehensive sandbox and framework for low-level system development, utilizing QEMU to simulate hardware environments without the need for physical devices. The environment integrates cross-compilation toolchains using Buildroot and crosstool-NG to target x86_64, ARMv7, and ARMv8 platforms from a single host. It features a specialized kernel debugging framework that leverages GDB an

This project is an OpenWrt firmware builder and specialized Linux router distribution designed to repurpose Amlogic S9xxx series hardware into functional routers. It provides a hardware adaptation layer consisting of kernel modifications and drivers that enable the operating system to run on Amlogic ARM SoC devices. The project features an automated firmware pipeline for scheduling, building, and distributing custom images. It includes a device recovery toolkit for bootstrapping, flashing, and restoring factory images, and supports the conversion of devices previously running different mobile

This project is a tutorial and framework for building a low-level, bare-metal operating system from scratch using the Rust language. It focuses on ARMv8 kernel development specifically for the Raspberry Pi 3, providing the resources necessary to implement a monolithic kernel that runs directly on hardware without an underlying operating system. The project distinguishes itself by providing a complete embedded cross-compilation suite within a containerized environment to ensure consistent builds. It includes a dedicated kernel deployer that uses a serial interface and chainloader to load and b