Put daily Handmade Hero source code in git

hh_to_git.sh

#!/bin/bash

repo="HandmadeHero"
source="source"

if [ ! -d "$repo" ]
then
	git init "$repo"
fi

cd "$repo" 
 
folders=($(ls "../$source" | sort))
last_tag=$(git tag | sort | tail -n 1)
if [ -z "$last_tag" ] 
then
	last_day="0"
else
	last_day="${last_tag:3:3}"
fi


for i in "${folders[@]}"
do
	day="${i:18:3}"
	
	folder="../$source/$i"
	tag="day$day"

	if [ "$day" -gt "$last_day" ]
	then
		cp -a "$folder/"*  .
		git add .
		git commit -am "Importing code for day $day" &&
			git tag "$tag"
	fi
done

Here's a fork that takes in a argument for a zip file, and does some things differently: https://gist.github.com/MattWoelk/32d1681bc69e0d0d06ee

I've improved a bit you're script:
https://gist.github.com/nsenica/cbc5a4975666d7b02164

It supports incremental updates, and "gitignores" the sources files.