Hagit is a git clone that can do some git operations most notably cloning a repository. In this write-up I go through the journey of creating this clone using Haskell whilst following the codecrafters course build your own git. Think of the course as, you have a task to do, and you research it to implement it.
This is mostly done as a fun activity. I wanted to try out how practical Haskell is to wield in the real world. Haskell has always fascinated me with its simplicity and elegance when it comes to contrived examples that haskeller's like to showcase, but I wanted a taste of it beyond that. This goes without saying, but I am a Haskell beginner as I have observed it from the sidelines from time to time.
Choice of implementing Git, basically boils down to me being curious about it and it sounded fun.
Before continuing I want to line out what you can expect from this article. We will dig into some of the git internals first by playing around with some git commands that are not commonly used when using it as a VCS and by chaining these commands we will get to the functionality of the commands that usually you (dear git user) interact with. Along the way, we will develop a better understanding of git internals. Moreover, I will also showcase some important bits from the Haskell implementation that I ended up with after doing so myself. If you choose to follow along in your language of choice you will also have a working toy-clone of git, that you can use as a VCS (barely).
- Familiarity with git is required as I won't be explaining what git is and how to use it.
- I will deep dive into some of the git internals, so their know how is not required.
- If you want to read the implementation as well (which is not required as I document the details of each step extensively) then you need to be familiar with Haskell.
We now have a subset of git operations working on our home grown git clone. In doing so we also got a taste for practical Haskell programming beyond the basics. From here we can improve upon this implementation quite a bit as we did skip implementing quite a few features.