#!/usr/bin/env bash

function fetch (){
  local rev=$1
  local output=$2
  local url=${3:-https://github.com/NixOS/nixpkgs.git}

  echo
  echo
  echo "update $url to rev $1"
  nix-prefetch-git \
    --url  ${url} \
    --rev ${rev} \
    > ${output}

}

fetch "refs/heads/nixos-21.05" .channelStable.json
fetch "refs/heads/nixos-unstable" .channelUnstable.json
fetch "refs/tags/v3.2.0" .nix-writers.json "https://cgit.krebsco.de/nix-writers/"
fetch "ef1e4480cf8af45cfdeac597b2f1b1af33923e93" .nixos-generators.json "https://github.com/nix-community/nixos-generators.git"