This issue records the latest news and shareable content about Zephyr, published in the last week of each month.
This magazine is open source (GitHub: lgl88911/Zephyr_Fans_Monthly[1]), and contributions, issue submissions, or recommendations for Zephyr content are welcome.
Project Data
Recent Developments:
- Release of Zephyr 4.2.0[2]
- Enhanced Power Management[3]
- SDK 0.18 will support LLVM[4]
News & Events
1、Zephyr + Dronecode Foundation Community Meetup[5]
The Zephyr + Dronecode Foundation Community Meetup will be held on July 8, 2025, in Guadalajara, Mexico.
2、2025 Zephyr Developer Summit[6]
The 2025 ZDS will be co-located with the Open Source Summit Europe, taking place from August 25 to 27, 2025, at the RAI Convention Center in Amsterdam, Netherlands.
3、Release of Zephyr 4.2.0[7]
Zephyr v4.2.0 is scheduled for release on July 18, 2025, with support until March 18, 2026. Major changes include:
- Support for Renesas RX architecture
- New USB Video Class driver
- Introduction of Power Harness testing in Twister, using hardware power monitors for automated data collection and analysis for current detection and result validation
- Full support for MQTT 5.0
- New HFP/AG/HF in Bluetooth stack
- zbus API updated to 1.0.0, API status stabilized
- Added 96 mainboards and 22 expansion boards
For more details, see the Zephyr V4.2.0 release.
4、IAR’s Production-Level Support for Zephyr RTOS[8]
IAR has released the Arm 9.70 toolchain, officially providing production-level support for Zephyr RTOS starting from this version.
5、tiny-curl to Support Zephyr Soon[9]
wolfSSL is set to port the lightweight HTTPS client tiny-curl to Zephyr RTOS.
Abstracts & Insights
1、Why Zephyr RTOS with IAR is a Smart Choice for Embedded Development Teams[10]
Zephyr offers open-source portability, breaking hardware bindings; IAR injects production-level capabilities (security certification + advanced debugging + automation processes), achieving a seamless transition from “flexible development to efficient production”.
This article shows that IAR has begun commercial promotion of Zephyr.
2、5 Tips for Mastering Zephyr RTOS[11]
The article explains the following aspects:
- Master modern build toolchains
- Be proficient in hardware abstraction layers
- Deeply understand kernel mechanisms
- Efficient debugging techniques
- Systematic learning paths
3、BTA Hiring Senior Embedded Software Engineer[12]
BTA is a company focused on ASIC and FPGA design and verification, as well as embedded software development services. Their job requirements mention Zephyr experience, indicating a demand for Zephyr services.
4、OpenAI Hiring Embedded Software Engineer[13]
OpenAI is hiring an embedded software engineer, with preference given to those with Zephyr experience.
Courses & Tutorials
1、Learning Zephyr Threads[14]
This is an introductory article on Zephyr, where the author analyzes the philosopher problem example using Tracealyzer to learn and understand Zephyr’s scheduling mechanism. It teaches how to use Tracealyzer to analyze the thread scheduling process in Zephyr.
2、Porting Zephyr to G32R501[15]
A hobbyist has ported Zephyr to the G32R501 from Zhuhai Jihai Semiconductor, with the porting repository available at https://gitee.com/quincyzh/g32r5_zephyr.
The article was published by Geehy Semiconductor on Hackster. It is not confirmed whether the porting was done by Jihai’s own personnel. For SoC porting, it is best to have continuous support from the original manufacturer and integrate into upstream; relying on hobbyists for sustainability is not strong.
3、Porting Zephyr to CH32V303[16]
This article demonstrates how to add new SoCs and new mainboards in the Zephyr operating system using CH32V303 as an example. The demonstration has already been merged into the Zephyr upstream.
Technologies & Tools
1、Kenning and Zephyr’s AutoML Accelerator Collaborative Optimization[17]
As a foundational RTOS, Zephyr provides a portable, hardware-abstracted deployment environment for AutoML, enabling seamless adaptation to complex AI accelerators and significantly lowering the development threshold for edge AI.
2 Exploring SLIP Networking over UART with Zephyr and Linux[18]
Using the SLIP framework on Zephyr RTOS to establish network connections between UART and Linux.
3 Zephyr GPT Intelligent Assistant[19]
An intelligent assistant tailored for Zephyr RTOS, built and optimized based on OpenAI’s GPT-4 architecture. It answers technical questions regarding Zephyr RTOS kernel, device model, Devicetree, Kconfig, driver development, west build system, providing device tree configurations, code templates, and driver examples, with real-time access to Zephyr official documentation[20] and bootlin[21], ensuring content is authoritative and up-to-date.
4、Static Scanning of Zephyr[22]
Coverity Scan static analysis of Zephyr’s defects shows that Zephyr outperforms the average of open-source projects in various aspects, proving the quality of Zephyr.
Zephyr: A total of 5,065,614 lines of code, with a defect density of 0.22 (defect density measured by the number of defects per 1,000 lines of code). Open-source project statistics:
- Less than 100,000 lines, 0.35
- 100,000 to 500,000 lines, 0.5
- 500,000 to 1,000,000 lines, 0.7
- More than 1,000,000 lines, 0.65
High-risk defects are concentrated in drivers, networking, and Bluetooth, with the most defects found in drivers.
Zephyr resolves defects faster than they are generated.
The average defect density of OSS during the same period is 0.65, while Zephyr peaks at 0.5 and maintains around 0.3 after 2025.
Zephyr Monthly Knowledge
1、bootlin has started providing online code browsing for Zephyr, similar to the Linux Kernel, which can be accessed at: https://elixir.bootlin.com/zephyr
References
[1]
lgl88911/Zephyr_Fans_Monthly: https://github.com/lgl88911/Zephyr_Fans_Monthly
[2]
Release of Zephyr 4.2.0: https://github.com/zephyrproject-rtos/zephyr/releases/tag/v4.2.0
[3]
Enhanced Power Management: https://github.com/zephyrproject-rtos/zephyr/issues/84049
[4]
SDK 0.18 will support LLVM: https://github.com/zephyrproject-rtos/zephyr/issues/3689
[5]
Zephyr + Dronecode Foundation Community Meetup: https://www.zephyrproject.org/what-to-expect-at-the-zephyr-project-dronecode-foundation-community-meetup-july-8-2025-guadalajara-mexico/
[6]
2025 Zephyr Developer Summit: https://www.zephyrproject.org/zephyr-developer-summit-2025-preview-whats-new/
[7]
Release of Zephyr 4.2.0: https://www.zephyrproject.org/zephyr-rtos-4-2-now-available-introduces-renesas-rx-support-usb-video-class-and-more/
[8]
IAR’s Production-Level Support for Zephyr RTOS: https://www.presseagentur.com/iar/detail.php?pr_id=7409&lang=en
[9]
tiny-curl to Support Zephyr: https://www.wolfssl.com/coming-soon-tiny-curl-for-zephyr-rtos/
[10]
Why Zephyr RTOS with IAR is a Smart Choice for Embedded Development Teams: https://www.iar.com/zh/blog/why-zephyr-rtos-with-iar-is-a-smart-choice-for-embedded-teams
[11]
5 Tips for Mastering Zephyr RTOS: https://www.designnews.com/embedded-systems/5-tips-for-mastering-zephyr-rtos
[12]
BTA Hiring Senior Embedded Software Engineer: https://www.simplyhired.ca/job/w7k0Q5uVP9wnmiJcwfLnolmt0vE3iANzF4YBwbjIW8nsmI-0GSruNw
[13]
OpenAI Hiring Embedded Software Engineer: https://nploy.net/jobs/it-and-technology/san-francisco/embedded-software-engineer/3866pen
[14]
Learning Zephyr Threads: https://www.zephyrproject.org/what-i-learned-about-zephyr-rtos-threads/
[15]
Porting Zephyr to G32R501: https://www.hackster.io/geehysemiconductor/here-it-is-zephyr-is-now-available-for-the-g32r501-32b0ca
[16]
Porting Zephyr to CH32V303: https://bootlin.com/blog/step-by-step-guide-to-adding-soc-and-board-support-to-zephyr-with-ch32v303/
[17]
Kenning and Zephyr’s AutoML Accelerator Collaborative Optimization: https://www.zephyrproject.org/extending-automl-features-in-kenning-and-zephyr-for-platforms-with-custom-ai-accelerators/
[18]
Exploring SLIP Networking over UART with Zephyr and Linux: https://swedishembedded.com/developers/connectivity/slip
[19]
Zephyr GPT Intelligent Assistant: https://chatgpt.com/g/g-adrA62xJn-zephyros-gpt
[20]
Zephyr Official Documentation: https://docs.zephyrproject.org/
[21]
bootlin: https://elixir.bootlin.com/zephyr/v4.2.0/source
[22]
Static Scanning of Zephyr: https://scan.coverity.com/projects/zephyr