Zephyr RTOS 4.4 Update: WireGuard, Wi-Fi Direct, and OpenRISC

The Zephyr Project, a Linux Foundation-hosted open-source RTOS effort, has released Zephyr RTOS 4.4, adding native WireGuard VPN support, Wi-Fi Direct peer-to-peer networking, and initial OpenRISC architecture support in what is now the project’s latest stable release. The update also brings Zephyr SDK 1.0, moves the minimum C language baseline to C17, and adds support for 121 new boards and 31 new shields.

Zephyr RTOS 4.4 expands connectivity

For embedded developers, the networking changes are the obvious headline. Wi-Fi Direct support allows devices to discover and connect without a conventional access point, which could be useful for commissioning, field provisioning, and short-range device-to-device links. Native WireGuard support adds low-overhead encrypted tunneling, giving Zephyr-based systems another option for secure remote access and protected data transport. The project has published both the release announcement and the full release notes.

Zephyr RTOS 4.4 broadens architecture and tools

Zephyr RTOS 4.4 also adds OpenRISC support, initially in 32-bit form, which extends the operating system’s reach into open-hardware, FPGA, and custom silicon work. On the toolchain side, Zephyr SDK 1.0 introduces experimental Clang/LLVM support and bundles OpenOCD and QEMU across the main host operating systems. The move to C17 is not dramatic in itself, but it does clean up the project’s baseline and makes newer language features easier to use consistently.

There is also a fair amount here for developers who care less about headline features and more about day-to-day workflow. The release adds a new build dashboard, heap hardening options, scope-based cleanup helpers for C, a ztest benchmarking framework, and broader USB host support including UVC cameras. Zephyr says an updated Cortex-M context-switch path can deliver an average 8% gain in the standard thread benchmark, which is the sort of small but useful change that matters in mature embedded codebases.

Support window matters as much as features

This is the first release under Zephyr’s new six-month cadence, with major versions now planned for April and October. That should make upgrade planning a bit more predictable for commercial users. The project says 931 individuals contributed to the release. As previously reported by eeNews Europe when Zephyr RTOS got closer to safety certification, the community is also trying to position the platform for longer-term industrial use. For teams making support decisions now, the support table shows that 4.4 is the latest stable branch, supported until 12 April 2027, while 3.7 remains the current LTS line.