Open-source alternatives to LiteOS

AliOS-Things is a scalable operating system for internet-connected devices. It provides an embedded firmware framework and runtime for managing hardware peripherals, network connectivity, and secure data execution across diverse CPU architectures. The system includes an edge AI inference engine for processing audio and image patterns locally without cloud dependencies. It also features a cloud connectivity SDK for automated onboarding, remote diagnostics, and log reporting, alongside a scripting engine for executing high-level code on resource-constrained hardware. Connectivity is handled th

YASB is a customizable status bar framework and desktop shell component for Windows. It provides a toolkit for building personalized information bars using a modular class-based widget architecture and CSS-based styling. The framework distinguishes itself through deep integration with Windows tiling window managers, allowing users to display active workspaces, tiling layouts, and window focus states. It also features automated visual consistency by generating system color schemes based on the current desktop wallpaper. The project covers a wide range of capabilities, including real-time syst

OpenCat-Quadruped-Robot is a development framework and motion control API for building four-legged robots. It provides a comprehensive environment for quadruped robot development, featuring tools for locomotion gait design, inverse kinematics, and a layered control architecture that separates high-level intelligence from low-level motion. The project distinguishes itself as an embedded AI deployment tool, allowing users to train, quantize, and deploy machine learning models to vision modules for tasks such as object detection and visual target tracking. It further supports complex human-robot

FreeRTOS is a real-time operating system for embedded devices that provides a kernel for predictable task execution. It utilizes priority-based preemptive scheduling and deterministic timing to manage simultaneous hardware tasks. The project includes a symmetric multiprocessing kernel that distributes processing workloads across multiple CPU cores using a shared memory architecture. It also provides a thread-safe TCP/IP networking stack for managing internet protocol traffic and IPv6 connectivity on embedded processors. The system incorporates an embedded memory manager with fixed-size alloc

Nanopb is a lightweight C implementation of Protocol Buffers designed for resource-constrained systems and microcontrollers. It functions as both an embedded serialization library for encoding and decoding structured data and a code generator that transforms definition files into compact C source and header files. The project is distinguished by its focus on static memory allocation, using fixed maximum sizes for strings and arrays to avoid dynamic memory allocation and heap fragmentation. It employs a callback-based streaming mechanism to process messages or fields that exceed available phys

Zig is a general-purpose systems programming language designed for high-performance applications that require manual memory management and direct control over hardware resources. It prioritizes predictable execution by enforcing explicit control flow and requiring functions to accept explicit memory allocators, ensuring that all heap operations and logic paths remain visible to the developer. The language distinguishes itself through a powerful compile-time metaprogramming engine that allows for arbitrary code execution during the build process, enabling advanced reflection and the generation

This project is firmware for the ESP8266 microcontroller that enables the sending and receiving of infrared signals to control consumer electronics. It functions as an infrared signal decoder and encoder, providing a network gateway through an MQTT bridge as well as TCP and web servers for remote wireless device control. The system supports the capture of raw infrared transmissions into memory buffers for analysis and playback, allowing for the reverse engineering of unknown protocols. It includes specialized capabilities for managing air conditioners via complex infrared sequences and generi

tmk_keyboard is keyboard firmware for AVR and Cortex-M microcontrollers designed to handle key matrix scanning and HID communication. It functions as an embedded hardware control library for managing GPIO pins and EEPROM storage, as well as a driver that transmits keystroke and mouse data to a host computer via USB or PS/2 protocols. The project features a layer-based keymap engine that allows physical keys to be mapped to multiple virtual layers. It also includes a legacy keyboard protocol translator to convert signals from vintage hardware standards to modern computer interfaces. The firmw

ZIO is a functional effect system for the JVM that models asynchronous and concurrent programs as pure, composable values with typed error handling and dependency injection. Its core identity is built on fiber-based concurrency, where lightweight, non-blocking fibers execute millions of concurrent tasks with structured lifecycle management, and a dual-channel error model that separates expected business failures from unexpected system defects at compile time. The system provides effect-typed dependency injection through a layer-based dependency graph, pull-based reactive stream processing with

p-queue is a JavaScript promise queue and concurrent task scheduler designed to limit the number of active asynchronous operations. It serves as an asynchronous rate limiter and promise lifecycle manager to prevent resource exhaustion. The project distinguishes itself through priority-based task scheduling and token-bucket rate limiting to control execution frequency. It integrates with abort signals for task cancellation and provides mechanisms to pause, resume, and clear pending operations. The tool covers broader traffic management capabilities including operation timeouts and concurrency

Concurrent Ruby is a comprehensive concurrency toolkit for the Ruby language that provides thread-safe data structures, synchronization primitives, and asynchronous execution patterns. It implements core concurrency abstractions including an actor model framework where isolated actors communicate through asynchronous message passing, a future and promise system for composing non-blocking operations, and thread pool executors that manage reusable worker threads for concurrent task execution. The library distinguishes itself through a broad set of coordination mechanisms that go beyond basic th

AsyncEx is a .NET asynchronous synchronization library providing a collection of primitives to coordinate tasks and manage execution flow. It implements mechanisms for asynchronous resource locking, event signaling, and concurrency control to ensure correct execution order in environments supporting async/await. The library includes an asynchronous lock implementation to protect shared resources without blocking threads, an async semaphore controller to limit simultaneous operations, and an event signaling system to manage the startup and shutdown of asynchronous workflows. The toolkit cover

This project is the official documentation site and communication standard portal for the MQTT messaging protocol. It serves as a central hub for technical specifications and implementation guidelines designed for lightweight messaging in internet-of-things environments. The site is implemented as a static website, utilizing static site generation and markdown-based content authoring to distribute protocol specifications and technical standards. The resources cover a broad range of industrial messaging and connectivity capabilities, including publish-subscribe routing, quality-of-service del

jsmn is a lightweight JSON parser library written in C. It provides zero-copy tokenization and incremental parsing designed for use in embedded systems and memory-constrained environments. The library identifies structural JSON elements by providing offsets into the original string rather than allocating new memory for data. It uses a single-pass scanning method and requires static-buffer allocation, meaning the caller provides the memory for tokens to avoid dynamic allocation during the parsing process. The parser supports incremental streaming, allowing it to process JSON data in chunks fr

CppGuide is a curated collection of educational resources and practical guides focused on C++ server development, Linux kernel internals, concurrent programming, network protocols, and security exploitation. It provides structured learning paths for backend developers, covering everything from interview preparation to building high-performance network servers and understanding operating system fundamentals. The guide distinguishes itself by offering in-depth, hands-on tutorials that walk through real-world implementations, including building a Redis-like server from scratch, designing custom

This is an open-source, crowd-sourced wiki textbook that teaches Linux system programming in C. It covers the core operating system concepts of process management through the fork-exec-wait model, dynamic memory allocation using implicit free list heap allocators, inode-based file systems, inter-process communication via pipes and shared memory, POSIX threads with synchronization primitives, signal-based asynchronous notification, virtual memory with page table translation, and runtime diagnostics using Valgrind and GDB. The textbook distinguishes itself by providing practical, implementation

smoltcp is a TCP/IP stack and network protocol implementation designed for resource-constrained environments and bare-metal hardware. It provides a set of socket interfaces for managing reliable TCP stream connections and connectionless UDP datagrams without relying on a standard library. The project utilizes a fixed memory layout and static memory allocation to manage network state and process packets without a dynamic memory allocator. It includes specialized capabilities for low-power wireless networks, such as header compression and fragmentation for 6LoWPAN. The stack covers the data li

NuttX is a POSIX-compliant real-time operating system designed for resource-constrained embedded environments. It functions as a scalable microcontroller OS that provides a Unix-like environment for managing hardware and running applications across architectures ranging from 8-bit to 64-bit. The system ensures high software portability by implementing a kernel that follows POSIX and ANSI standards. This allows developers to create portable embedded applications using standardized API calls across diverse hardware architectures. The project includes a modular kernel architecture and a hardwar

This project is an infrared communication library and hardware driver for Arduino microcontrollers. It provides the core systems necessary to send and receive infrared signals, acting as both a signal decoder that parses light pulses into structured addresses and commands, and a signal generator for transmitting codes. The library enables the capture of raw timing data to analyze unknown infrared protocols and recreate specific communication patterns. It supports the transmission of codes using predefined protocols, custom encoding schemes, or raw timing arrays. The system covers a broad ran

XNU is a hybrid operating system kernel that combines a microkernel architecture with a monolithic layer for system services. It provides a foundation for operating system development, incorporating standardized system-call interfaces, a modular device driver framework, and mandatory access control security. The architecture features a Mach-based microkernel and a BSD-based monolithic layer. It utilizes a message-passing inter-process communication bus for secure data exchange between isolated kernel components and user-space processes, alongside an object-oriented driver framework that decou

Gotop is a terminal-based system monitor and resource dashboard built with the Go programming language. It serves as a text-based user interface for real-time tracking of hardware resources, network activity, and running processes. The application provides a performance dashboard featuring graphical widgets for CPU and memory metrics. It includes a process manager that allows users to list, sort, and terminate active system processes based on their resource consumption. The interface supports customization through theme styling and layout configurations, enabling users to adjust color scheme

Blynk is an embedded device framework and IoT cloud connectivity library designed to establish secure, bi-directional communication between microcontrollers and a remote management platform. It provides the core identity of an IoT device management tool, enabling the synchronization of device states, remote hardware control, and the mapping of hardware data to cloud-based interfaces. The project distinguishes itself through a virtual-pin system that decouples cloud communication from physical pins, allowing for hardware-independent data exchange. It also supports advanced architectural offloa

probe-rs is an embedded debugging toolset used for flashing, debugging, and inspecting microcontrollers via hardware debug probes. It functions as an embedded firmware flasher, a memory manager for reading and writing to processor registers, and a server implementing the Debug Adapter Protocol to connect hardware debugging to various code editors. The project includes a CMSIS-Pack target parser to extract device metadata and flash configurations from industry-standard definition files. It provides a driver-based probe abstraction to interact with various hardware debug probes regardless of th

Blinker is an IoT cloud connectivity library designed to link embedded hardware to cloud services. It functions as a communication layer that connects physical devices to mobile applications for remote triggering, state monitoring, and remote data transmission. The library provides a development framework for ESP32 microcontrollers and a set of tools for interfacing Arduino R4 hardware with cloud backends. It enables the establishment of secure links between embedded devices and cloud services to store and transmit data remotely. The project includes capabilities for remote hardware manageme

TrafficMonitor is a system performance monitor that provides a floating desktop window and taskbar overlay to track real-time CPU, memory, and network speed metrics. It functions as a customizable system overlay and hardware resource tracker, displaying live statistics and user-defined data through transparent desktop widgets. The project uses a plugin-based system and dynamic-link libraries to extend data sources and add new hardware tracking capabilities. It includes a theme engine that reads external configuration files to apply custom skins, fonts, and background colors to the interface.

This project is an IoT cloud integration SDK and C++ library designed to connect ESP32 hardware to a remote management service. It provides a communication bridge that enables real-time, bidirectional data exchange between embedded devices and remote clients. The library utilizes a cloud-relay communication model and key-based device authentication to secure the connection between hardware and the cloud. It includes a dedicated provisioning tool for securely transferring wireless network credentials to devices during initial setup. The framework integrates directly with the ESP-IDF developme

Blackmagic is a GDB server for embedded hardware that translates GDB remote protocol messages into JTAG and SWD commands. It functions as an ARM and RISC-V debugger and hardware debug probe manager, enabling users to inspect memory, control execution, and manage registers on ARM Cortex and RISC-V cores. The project distinguishes itself by acting as a remote hardware debugging bridge that can stream GDB server traffic over TCP/IP to control physical hardware from a remote machine. It also provides a JTAG and SWD interface to connect host computers to target hardware and serves as an embedded f