## Meta-mender Kirkstone branch released!

Finally the **kirkstone** branch of meta-mender, Mender's [Yocto Project](https://yoctoproject.org/?target=_blank) layer, has been released. The main feature of this release is compatibility with the Yocto branch of the same name, which is [their latest LTS release](https://wiki.yoctoproject.org/wiki/Releases?target=_blank). Branches in meta-mender are maintained according the same schedule, which means that the meta-mender kirkstone branch is an LTS release, supported until at least April 2024.

At the same time, support for the **zeus** and **warrior** branches is dropped. We still accept pull requests for them, but they become community maintained, and are no longer supported by Mender.

In addition to compatibility, there are numerous smaller features, additions and changes contained in this release, some of which require adjustments to existing build configurations. Below is a breakdown of the most important ones.

### Default Update Modules

Several Update Modules are now installed by default. [Update Modules](https://docs.mender.io/client-installation/use-an-updatemodule?target=_blank) allow different types of updates besides the built-in rootfs update mechanism, such as updating single files, installing entire folders, installing packages, or updating Docker containers.

These Update Modules are installed by default

* [deb](https://hub.mender.io/t/deb-packages/326?target=_blank)
* [directory](https://hub.mender.io/t/directory/325?target=_blank)
* [docker](https://hub.mender.io/t/docker/324?target=_blank)
* [rpm](https://hub.mender.io/t/rpm-packages/494?target=_blank)
* [script](https://hub.mender.io/t/script/328?target=_blank)
* [single-file](https://hub.mender.io/t/single-file/486?target=_blank)

To disable the automatic installation of these Update Modules, add `PACKAGECONFIG_remove = "modules"` to your `mender_%.bbappend` file, or set `PACKAGECONFIG` explicitly.

### `MENDER_CERT_LOCATION` variable deprecated/removed

The `MENDER_CERT_LOCATION` has been deprecated and removed. To install a custom certificate for the client, either install it through another recipe into the `ca-certificates` area, or make a `mender-server-certificate.bbappend` recipe and add `SRC_URI = "file://server.crt"` to it.

### grub-mender-grubenv tools renamed

Mender's tools for manipulating the boot environment when [GRUB](https://www.gnu.org/software/grub/?target=_blank) [integration](https://docs.mender.io/system-updates-yocto-project/board-integration/bootloader-support/grub?target=_blank) is enabled, have been renamed. This was done to avoid conflict with the u-boot-fw-utils package, whose tools have the same names. The tools, which used to be named `fw_printenv` and `fw_setenv`, are now called `grub-mender-grubenv-print` and `grub-mender-grubenv-set`, respectively.

This is unlikely to affect many users unless you have scripts which use the same tools.

However, it means that it is now possible to install the grub-mender-grubenv and u-boot-fw-utils packages at the same time. This can be useful in certain advanced ARM board scenarios where U-Boot is used to load GRUB as a UEFI app, and access to both boot environments is needed.

### Support for systemd-boot

It is now possible to use systemd-boot with mender by turning off `mender-grub` and `mender-uboot` features and turning on `mender-systemd-boot`:

```
MENDER_FEATURES_DISABLE:append = " mender-grub mender-uboot"
MENDER_FEATURES_ENABLE:append = " mender-systemd-boot"
```

Note that this is a contributed feature, and it is not officially supported by Mender.

### Mender-binary-delta

It is no longer necessary to unpack the `.tar.xz` file before including Mender's [mender-binary-delta software](https://hub.mender.io/t/robust-delta-update-rootfs/1144?target=_blank) in the Yocto build. In fact, it is no longer supported. Lines starting with `FILESEXTRAPATHS_pn-mender-binary-delta` should be removed from the configuration and replaced with the line below instead.

```
SRC_URI:pn-mender-binary-delta = "file://${HOME}/mender-binary-delta-1.4.0.tar.xz"
```

Adjust the file path to where your `.tar.xz` file is. Note that the two slashes after `file:` are not part of the path. If you are providing an absolute path, there will be three slashes after `file:`.