After installing Nix from nix-installer, run just prepare to install nix LSP for editor support and nix formmater.
Then run just build-image to build RPi SD card image that contains OpenMower setup.
For MacOS users, prepend just command with ./inside-docker.sh, like ./inside-docker.sh just build-image.
Install jnoortheen.nix-ide VSCode extension for Nix language support.
If the built image does not boot with error before Linux kernel startup, you might need to update the RPi EEPROM.
First build SD card image with older kernel by changing kernel defition in base.nix to linuxPackages_6_0. After flashing the image run the following commands on the RPi:
sudo nixos-rebuild switch --flake .
nix-shell -p raspberrypi-eeprom
sudo mkdir /mnt
sudo mount /dev/disk/by-label/FIRMWARE /mnt
BOOTFS=/mnt FIRMWARE_RELEASE_STATUS=stable rpi-eeprom-update -d -a