algebra VS Git

Love seeing the work on modes! There's definitely a use for this in cryptography, where you might want to serialize things containing elliptic curve points, which can be serialized in both "compressed" form and "uncompressed" form. We make extensive use of this in our serialization framework in arkworks: https://github.com/arkworks-rs/algebra/tree/master/serialize

Rust takes the cake in the blockchain space: Substrate, Cosmos (CosmWasm), and Solana. All of the zero knowledge cryptography libraries used for layer 2 solutions are written in Rust, compiling to Wasm (see arkworks, Risc0). Ethereum's next version of smart contracts will even use a restricted subset of Wasm ("Ewasm") instead of EVM.

Is ark a prefix Embark is using for all their Rust crates, or is it a one-off name for your future crate? If so, it might collide with our naming convention in the arkworks ecosystem: arkworks.rs

You can take a look at our approach in the arkworks library: https://github.com/arkworks-rs/algebra/blob/920070c60d481a29fb3c262ef9579f34cbb053a6/ff/src/fields/macros.rs#L103

Look at any PR/patch series that got merged into the Git project. https://github.com/git/git/

Any random one. Because those that did not meet the minimum criteria for a well-crafted history would not have passed review.

Boy, I can't find this either (but also, the kernel mailing list is _really_ difficult to search). I really remember Linus saying something like "it's not a real SCM, but maybe someone could build one on top of it someday" or something like that, but I cannot figure out how to find that.

You _can_ see, though, that in his first README, he refers to what he's building as not a "real SCM":

https://github.com/git/git/commit/e83c5163316f89bfbde7d9ab23...

Here is the direct link, as HN somehow removes the query string: https://github.com/git/git/commits?author=peff&since=2023-10...

I understand all that.

I'm saying, if you write a survey and one of the possible answers is "diff", but you don't clearly define what you mean by "diff", then don't be surprised if respondents use any reasonable definition that makes sense to them. Ask an ambiguous question, get a mishmash of answers.

The thing that Git uses for packfiles is called a "delta" by Git, but it's also reasonable to call it a "diff". After all, Git's delta algorithm is "greatly inspired by parts of LibXDiff from Davide Libenzi"[1]. Not LibXDelta but LibXDiff.

Yes, how Git stores blobs (using deltas) is orthogonal to how Git uses blobs. But while that orthogonality is useful for reasoning about Git, it's not wrong to think of a commit as the totality of what Git does, including that optimization. (Some people, when learning Git, stumble over the way it's described as storing full copies, think it's wasteful. For them to wrap their heads around Git, they have to understand that the optimization exists. Which makes sense because Git probably wouldn't be practical if it lacked that optimization.)

The reason I'm bringing all this up is, if you're trying to explain Git, which is what the original article is about, then it's very important to keep in mind that someone who is learning Git needs to know what you mean when you say "diff". Most people who already know Git would tend to gravitate toward the definition of "diff" that you're assuming (the thing that Git computes on the fly and never stores), but people who already know Git aren't the target audience when you're teaching Git.

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[1] https://github.com/git/git/blob/master/diff-delta.c