Hacker News new | ask | show | jobs
by sfescape 2794 days ago
I'm surprised that it's not mentioned in the article that one of the most interesting architectural aspects of git is that it's a blockchain system.
4 comments

That's arguably not the most interesting architectural aspect of Git.

Or does any back-linked tree data-structure becomes interesting if the nodes keep a hash of their parent instead of a raw reference? I don't think that's the case.

It might be a bit heretical but I don't think Git has a super interesting internal architecture. I'm not downplaying the fact that Git was very innovative, especially considered the landscape of SVMs at the time. The tool as a whole is great and has desirable properties but its internals don't strike me as particularly innovative. It's a clever composition of solutions to well established problem domains. And in that aspect it is a beautiful engineering solution although there is room for a lot of improvement in terms of UX.

And in addition to that, I would argue that it would be a very weak definition of "blockchain". The innovation in Bitcoin is the incorporation of proof-of-work and resulting alignment of incentives such that it can achieve probabilistic consensus in an adverse setting and with some degree of asynchronicity.

The underlying structure of the data is an obvious choice because it is simple and "captures" the idea of aggregate global state, but it's also hardly an important innovation. UTXOs are more significant.

And also, recall that the textbook example for state-machine replication is always an append-only log for example. So that's not the crux of it, or of blockchain, in my humble opinion.

I said one of the most. I didn't declare it the most...
It's a merkle tree, not every hash tree or chain is a blockchain thing.

IMO blockchain describes the combination of a hash chain and the no-trust agreement protocol on top.

I don't agree with that. The oldest blockchain known has its hash codes published each week in the New York Times. I would agree that having the ability to prove the history hasn't been modified by externally retaining the hashes could be a component, but git qualifies for that as well.
I would recommend reading the Wikipedia article for a blockchain [0]. It's agreed that a blockchain is decentralized and resistant to change from bad actors. If a system doesn't meet those requirements, it's just a fancy database. I don't see how Git or the New York Times example you mentioned are inherently decentralized.

[0] https://en.wikipedia.org/wiki/Blockchain

The New York Times example is by the inventors of blockchain.

https://www.anf.es/pdf/Haber_Stornetta.pdf

Have a look at https://en.wikipedia.org/wiki/Linked_timestamping

This is technology from the 90s. The innovation of blockchain is the no-trust agreement protocol.

But when was the term 'blockchain' used for the first time?

This is just a matter of definition. You can call git blockchain or not, the only fact is that git shares the merkle tree property with Bitcoin.

This is from 2012, so it makes more sense to be surprised that it doesn't mention git being a crowdfunded, gamified, phablet-compatible cybertool as-a-service on the cloud.
It was written before “blockchain” was a well known term.
git predates the creation of bitcoin and 13 years after the invention of blockchain.