default.nix

let
  nixpkgs = builtins.fetchTarball "https://github.com/nixos/nixpkgs/archive/038afc6.tar.gz";
  pkgs = import nixpkgs {};
in {
  changeConfig = { bootconf, eeprom, ts }:
  pkgs.runCommand "eeprom.img" {
    buildInputs = [ pkgs.raspberrypi-eeprom ];
  } ''
    cp ${eeprom} pieeprom.bin
    mkdir $out
    # Apply config
    rpi-eeprom-config --config ${bootconf} --out $out/pieeprom.bin pieeprom.bin
    sha256sum $out/pieeprom.bin | cut -d' ' -f1 > $out/pieeprom.sig
    echo 'ts: ${ts}' >> $out/pieeprom.sig
  '';
}