RT-Thread is an open source IoT operating system.

Primary Git Repository for the Zephyr Project. Zephyr is a new generation, scalable, optimized, secure RTOS for multiple hardware architectures.

RIOT - The friendly OS for IoT

A curated list of awesome embedded programming.

Lua RTOS for ESP32

object-oriented C++ RTOS for microcontrollers

QP/C real-time embedded framework/RTOS for embedded systems based on active objects (actors) and hierarchical state machines

Trampoline is a static RTOS for small embedded systems. Its API is aligned with OSEK/VDX OS and AUTOSAR OS 4.2 standards.

Additions to FreeRTOS

A tiny Linux-like real-time kernel optimized for ARM Cortex-M chips

The core crate for Drone, an Embedded Operating System.

Apache NuttX is a mature, real-time embedded operating system (RTOS)

Lightweight ESP-AT parser library for host MCU. Establish communication with ESP8266 or ESP32 from any embedded system.

An open framework for micro-controller software

Library for SIMCOM GSM modules to communicate with AT commands and RTOS from host device

A C++, compile-time, reactive RTOS for the Stack Resource Policy based Real-Time For the Masses kernel

RTOS for microcontrollers

A high-performance, high-stability, cross-platform MQTT client, developed based on the socket API, can be used on embedded devices (FreeRTOS / LiteOS / RT-Thread / TencentOS tiny), Linux, Windows, Mac, with a very concise The API interface realizes the quality of service of QOS2 with very few resources, and seamlessly connects the mbedtls encryption library.

《Zephyr OS 文档 - 中文版》

A tiny real-time kernel focusing on formal reliability and simplicity.

揭秘 Zephyr OS

QP-nano real-time embedded framework/RTOS for embedded systems based on active objects (actors) and hierarchical state machines

QP/C++ real-time embedded framework/RTOS for embedded systems based on active objects (actors) and hierarchical state machines

Free real-time operating system (RTOS) designed for deeply embedded applications with advanced c++ wrapper

Embedded systems memory management library. Implementations for malloc(), free(), and other useful memory management functions

CLI utility for Drone, an Embedded Operating System.

合宙LuatOS -- Lua base RTOS, build for many embedded systems. LuatOS是运行在嵌入式硬件的实时操作系统

A POSIX-like OS for ARM processors.

ERIKA Enterprise v3 RTOS

Standard NuttX with current PX4 patches