RIOT

Supports over 200 boards across AVR, MSP430, ESP8266, ESP32, RISC-V, and ARM architectures, enabling deployment on diverse microcontrollers without API changes.

Allows native coding in C, C++, or Rust, and integrates runtimes like MicroPython and JavaScript, providing versatility for different development preferences and project needs.

Includes IPv6, 6LoWPAN, CoAP, MQTT, LoRaWAN, BLE, and more, as listed in the README, making it ideal for connected devices with complex protocol requirements.

Offers OTA updates via SUIT, PSA Cryptographic API, and DTLS/EDHOC, ensuring secure deployments for IoT applications directly from the feature set.

Uses a preemptive, tickless scheduler with priority-based task management, optimized for low-power and deterministic real-time operations per the system features.