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    A rebuttal, though from an OpenLibra contributor rather than Facebook.

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      I suspect Facebook’s longer term plans, were they to actually launch Libra, are to move to a permissionless proof-of-stake model […]

      some of the testnets we are running for other BFT protocols are operating at those performance levels or above

      Is it actually sound? I don’t know, it’s brand new and looks unfinished to me […]

      Right now Libra is missing many features of other proof-of-stake blockchains like governance, however these mechanisms can be used to implement things like payment reversals […]

      Nothing in the rebuttal other than the cryptography section sounds particularly strong.

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        The cryptography section isn’t wrong but it misses my point entirely. I claim that the more mission critical the cryptography is in a piece of software the more scrutiny it should be given and that these libraries are relatively new and not as tested as older ones. A company with resources like Facebook could have put a lot more resources into this and it would have been good for the Rust community for this to happen as it makes the whole ecosystem more robust.

        When you’re going before congress to testify that this system can safely handle private user data, the QA should be much higher on your software because the public’s interest is involved. I thought this was a fairly uncontroversial opinion.

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        the original: “these ideas are bad and incoherent, and this code cannot possibly implement reality consistently”

        the riposte: “but look how shiny the pieces are! also, it has to suck cos it’s a blockchain,”

        that’s really not a good rebuttal

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          I agree, it isn’t a rebuttal of my original points. It’s more a statement of blind faith that the technology just needs to be invented and that the public should just trust that currently intractable problems will just be somehow solved before it goes live. I don’t have any faith in blockchain tech, I only look at what exists and is provable today.

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          Thanks for finding this, always interesting to read a rebuttal on a similar level.

          For context, I am a contributor to OpenLibra, a group independent of Facebook (or should I say “FACEBOOK”)

          I struggle to understand the joke here, unless it’s a poke at cryptocurrency boosters to refer to conventional money as “FIAT” (in all caps).

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            Probably related to the rebrand.

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              Ah, I’ve missed that. Thanks. That is a fugly logo.

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          There’s some good meaty stuff about verifiability, types etc in the Move language which should interest many here who might otherwise be turned off by the tags.

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            This particuarly caught my interest as it’s only the second writeup I’ve seen of the technical side, and the first was the passing piece by Elaine Ou about how incomplete she thought the code dump was: https://www.bloomberg.com/opinion/articles/2019-06-20/facebook-s-libra-cryptocurrency-isn-t-actually-supposed-to-work

            She assumed it was technically incomplete because it was for the regulators, but what Libra gave the regulators was also ridiculously incomplete …

            I think the question now is really: what on earth were they doing in there for two years?

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            The libra project depends on several fairly new “wild west” libraries for building experimental cryptosystems that have only emerged in the last few years

            Uh, Curve25519 based stuff is everywhere, including TLS, SSH and Tor. It’s very much production quality. And dalek is a very good implementation that has been audited. This part of the article is terrible.

            As for everything else… yeah, typical cryptocurrency stuff.

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              Implementations, not algorithms.

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                I mentioned the implementations, as you can see.


                experimental cryptosystems

                reference sort of looks like it refers to the algorithms. Might be referring to the stuff they’re using the algorithms for, of course (“depends […] for building …” not “libraries [that are] for building …”) but whatever

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              This was already posted by @pushcx in a comment to the submission of the “unsound” post:


              I guess this should be folded into that submission…

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                I have to disagree, I wouldn’t have found it that way

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                  Well now it’s here, and there are some good comments on it!

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                There’s a third tech critique of Libra: https://twitter.com/mcclure111/status/1142496050177105923

                currently an epic Twitter thread, the author is cleaning it up to make it a blog post at some point