NixOS on ARM Examples

Examples of Nix expressions for cross compiling NixOS images for ARM

Customizing

If you want to setup wireless networking, public SSH keys or the like, copy custom.nix.template to custom.nix and edit its content to your requirements.

Building

Set BOARD_TYPE to the desired value and run the command as shown below.

$ export BOARD_TYPE=foobar
# nixpkgs pinned to master as of Thu Mar 31 08:01:29 2022 -0700
$ export NIXPKGS="https://github.com/NixOS/nixpkgs/archive/3e481ad.tar.gz"
$ nix-build -I nixpkgs=$NIXPKGS -I machine=machines/$BOARD_TYPE --out-link out-links/$BOARD_TYPE

Boards

BOARD_TYPE can be set to the name of any directory in machines.

Board	BOARD_TYPE
generic AArch64	generic-aarch64
generic ARMv7l	generic-armv7l-hf
ESPRESSObin	espressobin
Orange Pi Zero	orange-pi-zero
ROC-RK3328-CC	roc-rk3328-cc
Raspberry Pi Zero W	raspberry-pi-zero-w

Building All

Run this command to build images for all available boards. I just added this section to have something to copy and paste for a "release build".

$ export NIXPKGS=https://github.com/NixOS/nixpkgs/archive/3e481ad.tar.gz
$ for machine in $(find machines -maxdepth 1 -mindepth 1 -type d)
do
    export BOARD_TYPE=$(basename $machine);
    nix-build -I nixpkgs=$NIXPKGS -I machine=machines/$BOARD_TYPE --out-link out-links/$BOARD_TYPE
done

Flashing

# set correct path for SD card
export SD_CARD=/dev/sda
# inflate image and write to SD card
zstd -dcf out-links/$BOARD_TYPE/sd-image/*.img.zst | sudo dd status=progress bs=64k iflag=fullblock oflag=direct of=$SD_CARD && sync && sudo eject $SD_CARD

Attribution

• repo inspired by illegalprime/nixos-on-arm
• mirrexagon wrote a Nix expressions for building u-boot for the ESPRESSObin
• big thanks to sternenseemann for helping me with cross compilation