Zephyr 26.04 release notes

Zephyr 26.04 LTS is Canonical’s distribution of upstream Zephyr 4.4.

Development environment

The standard development path uses Workshop. Use the zephyr SDK from the 26.04/stable channel.

Source distribution

Canonical maintains the source repositories in the Zephyr RTOS Launchpad project. The Canonical west manifest pins the tested repository revisions. The current source set is published with the immutable 26.04.0 tag.

Known limitations

Workshop support requires an Ubuntu or snap-enabled Linux host. Use the host system installation path on an Ubuntu 26.04 host that cannot run Workshop.

Probe-based flashing over a USB debug probe does not work in Workshop 26.04. A custom-device plug with subsystem: usb can show as connected while the container receives no /dev/bus/usb/ device node. The flash tool then reports LIBUSB_ERROR_NO_DEVICE. A tty plug for the same board is unaffected. See the pass-through warning in the flash hardware tutorial.

The upstream pip model (pip install -r requirements.txt) does not work on a clean 26.04 image. It builds C extensions such as ruamel-yaml-clib from source, which requires python3-dev, a package that is not preinstalled. Install python3-dev or use the host install guide, which installs the Python requirements as packages.

See also