# Zephyr RTOS

14 Hacker News commenters recommended Zephyr RTOS and 5 criticized it, November 2025 to November 2026. It was recommended in 11 of 13 months. It meets the Hacker Approved badge rule.

**Verdict:** Recommended for broad board support, strong wireless and networking stacks, and a portable HAL. Critics mainly point to flash chip power management problems.

## Why people recommend it

- Strong wireless and networking stacks (5 comments): "an extremely capable RTOS with a decent shell, good features, and one of the best RTOS networking stacks out there" ([source](https://news.ycombinator.com/item?id=46338879)) "Zephyr blows away Arduino, it has portable stacks, security, update, wifi/ble, etc..." ([source](https://news.ycombinator.com/item?id=46337663)) "zephyr seems to be the embedded os with the best wireless support by a country mile" ([source](https://news.ycombinator.com/item?id=49100837))
- Supported on boards from many vendors (4 comments): "Their HAL works, their stacks work, the portability is incredibly smooth compared to other vendors." ([source](https://news.ycombinator.com/item?id=46338933)) "Come over to Zephyr and see all the stuff you can run on boards from basically everyone" ([source](https://news.ycombinator.com/item?id=46617888)) "every major embedded SOC/MCU maker supports it" ([source](https://news.ycombinator.com/item?id=46338950))
- Portable HAL that works well (3 comments): "Their HAL works, their stacks work, the portability is incredibly smooth compared to other vendors." ([source](https://news.ycombinator.com/item?id=46338933)) "Zephyr blows away Arduino, it has portable stacks, security, update, wifi/ble, etc..." ([source](https://news.ycombinator.com/item?id=46337663)) "Zephyr's HAL streamlines the latter. Very nice." ([source](https://news.ycombinator.com/item?id=46343343))
- Pragmatic choice for most embedded (2 comments): "10 years on a project then a full rewrite to zephyr - thats the move" ([source](https://news.ycombinator.com/item?id=47871801)) "Zephyr/C seema still the pragmatic choice for most embedded" ([source](https://news.ycombinator.com/item?id=49549881))

## Alternatives hackers recommend

- [QNX Neutrino RTOS](https://hackerapproved.com/p/qnx.md): 47 recommend
- [FreeRTOS](https://hackerapproved.com/p/freertos.md): 9 recommend
- [Hubris RTOS](https://hackerapproved.com/p/hubris.md): 6 recommend
- [MicroPythonOS](https://hackerapproved.com/p/micropythonos.md): 6 recommend
- [VxWorks](https://hackerapproved.com/p/vxworks.md): 5 recommend

## Cite as

Hacker Approved, "Zephyr RTOS", https://hackerapproved.com/p/zephyr-rtos/ (counts from 1,795,640 Hacker News comments, November 2025 to November 2026).