The porting guide requires img2simg and simg2img which are provided up to Ubuntu 22.04 and not later.
You can install these utilities using this snap:

sudo snap install android-platform-tools

sudo snap connect android-platform-tools:adb-support
sudo snap connect android-platform-tools:block-devices
sudo snap connect android-platform-tools:raw-usb
sudo snap connect android-platform-tools:removable-media
sudo snap connect android-platform-tools:network
sudo snap connect android-platform-tools:network-bind

sudo snap alias android-platform-tools.img2simg img2simg
sudo snap alias android-platform-tools.simg2img simg2img

The porting guide requires img2simg and simg2img which are provided up to Ubuntu 22.04 and not later.
You can install these utilities using this snap:

sudo snap install android-platform-tools

sudo snap connect android-platform-tools:adb-support
sudo snap connect android-platform-tools:block-devices
sudo snap connect android-platform-tools:raw-usb
sudo snap connect android-platform-tools:removable-media
sudo snap connect android-platform-tools:network
sudo snap connect android-platform-tools:network-bind

sudo snap alias android-platform-tools.img2simg img2simg
sudo snap alias android-platform-tools.simg2img simg2img

@faveoled that's where kernel config is stored. deviceinfo is outside of sources directory

@shadan write it line-by-line, fill some data from unpackbootimg

@shadan looks like there are two ways - one involves compiling full halium source, and the one I suggested involves just compiling your own kernel. I'd prefer the latter as I'm a newbie to this

@shadan are you using an old guide? I think you should use this instead:
https://docs.ubports.com/en/latest/porting/build_and_boot/standalone_kernel_build.html

Hello,
Could I use mkbootimg with externally compiled kernel (with the kernel config changes needed by halium) to create halium-boot.img?
The kernel requires some specific tooling. That's why I'm not following the official standalone kernel guide.
If it's possible, I need a way to create boot initramfs.