Subject: Re: [bitcoin-dev] On the experiment of the Bitcoin Contracting Primitives WG and marking this community process "up for grabs"

From: Antoine Riard <[email-masked]>
Date: Thu, 20 Jul 2023 06:46:25 +0100

Hi Greg,

I'm very meeting your development approach with regards to starting smalls
about consensus change primitives, and I think taproot has demonstrated
some good historical process, which has good archives about how development
was conducted (e.g the community-wide taproot review of which the Bitcoin
Contracting Primitives WG was built on this experience [0]).

I don't know about saying that the BOLTs (and its process) should be
authoritative over the running code of implementations. While it's
definitely a mark of some bar of technical review and inter-compatibility,
I think ultimately each BOLT has to be judged individually on its own
technical merits. And I think we had a bunch of cases in the past when "the
map is not the territory". Even there are few areas of critical Lightning
operations which are not documented by the BOLTs to the best of my
knowledge (such as fee-bumping and transactions broadcast reactions as it
was for on-chain DLCs [1]).

Lastly, there is a huge area of uncertainty about the technical fitness of
Simplicity for 2/small party channels. I remember a Russell O'connor
presentation about Simplicity back in Paris (2017 or 2018 ?) and asking him
how it would work in a chain of transactions, while the answer was iirc
"yes it has been designed with this constraint", it's a very open question
when you have off-chain states which advances in independence from the
on-chain state between a dynamic number of counterparties (kinda the
interactivity issue for payment pools). Here I guess you would have to come
to a consensus to the model of logic followed for the analysis of such
distributed systems e.g Leslie Lamport's temporal logic [2]. Additionally,
the theoretical foundations on the Coq prover are still actively studied by
Xavier Leroy at the College de France and some novel insights might be
interesting for using formal verification in terms of Bitcoin consensus
changes development (and I don't know if all the works and lessons have
been translated from French to English).

Best,
Antoine

[0] https://github.com/ajtowns/taproot-review
[1]
https://github.com/discreetlogcontracts/dlcspecs/blob/master/Non-Interactive-Protocol.md
[2] https://en.wikipedia.org/wiki/Temporal_logic_of_actions

Le mer. 19 juil. 2023 à 21:45, Greg Sanders <[email-masked]> a écrit :

> Hello Keagen,
>
> Most of the complexity of LN cannot be resolved with covenants. Of the
> things that can be simplified in my experience, you're going to need more
> than CTV to get significant gains. And in the end, channels can only get so
> simple since we have many other BOLTs to deal with. And even then, you're
> going to have to convince LN spec writers to include such changes, whatever
> they are, then get deployment.
>
> Step 1 is finding a primitive that seems interesting. It's important to
> moderate enthusiasm for any primitive with reality, and probably by being
> concrete by writing specs that use a primitive, and code it up to discover
> what we're overlooking. We're always overlooking something! In my humble
> opinion these are step 2 and 3 of gathering mind-share.
>
> As a more productive tact, if we're thinking beyond 2/small party
> channels, probably better to snap your fingers, pretend we have Simplicity,
> see what we can build, and work backwards from there to see if we can
> accomplish this within the confines of bitcoin script?
>
> Cheers,
> Greg
>
> On Wed, Jul 19, 2023 at 3:59 PM Keagan McClelland via bitcoin-dev <
> [email-masked]> wrote:
>
>> Hi Antoine,
>>
>> Thank you for the effort you've put towards this. I generally agree that
>> a smooth functioning Lightning Network is of greater importance than
>> advanced contracting capabilities. However, as I dive deeper into some of
>> the more ambitious goals for LN development I am learning that a great deal
>> of complexity of some current lightning (LN) proposals can be handily
>> discharged with CTV. While I am not intimately familiar with all of the
>> other covenant schemes to the same level of technical proficiency, I have a
>> suspicion that a number of them, if not all of them, are capable of
>> discharging the same flavor and amount of complexity as well. Others should
>> chime in if they can confirm this claim.
>>
>> I have been publicly on the record as supporting the addition of some
>> covenant scheme into Bitcoin for some time and have long held on
>> theoretical grounds that the addition of such a mechanism is both necessary
>> and inevitable if Bitcoin is to survive in the long term. However, as I've
>> started to work more directly with the Lightning protocol, these
>> theoretical and purely logical arguments became far more concrete and
>> immediately beneficial.
>>
>> I say this primarily to challenge the idea that covenants are a
>> distraction from lightning development. It may very well be that your areas
>> of focus on LN preclude you from splitting your attention and none of this
>> email should be interpreted as a criticism of you applying your efforts in
>> the highest leverage manner you can manage. That said, I don't want
>> observers of this thread to walk away with the impression that they are two
>> independent efforts as covenants can significantly contribute to LN's
>> maturity. When and how should they be prioritized? Unfortunately I don't
>> feel able to comment on that at this time. All I know is that Lightning
>> would almost certainly benefit substantially from having a covenant
>> primitive.
>>
>> Cheers,
>> Keags
>>
>> On Tue, Jul 18, 2023 at 3:40 PM Antoine Riard via bitcoin-dev <
>> [email-masked]> wrote:
>>
>>> Hi list,
>>>
>>> Last year amid the failure of the CTV speedy trial activation and
>>> intense conversations about a rainbow of covenant proposals, I introduced
>>> the idea of a new community process to specify covenants [0]. This post is
>>> to resume the experiment so far and officially mark the process maintenance
>>> as "up for grabs", as I won't actively pursue it further (after wavering on
>>> such a decision a bit during May / June).
>>>
>>> Few of the goals announced at that time were to build a consistent
>>> framework to evaluate covenant proposals, see the common grounds between
>>> proposals if they could be composed or combined by their authors, open the
>>> consensus  changes development process beyond the historical boundaries of
>>> Bitcoin Core and maintain high-quality technical archive as a consensus
>>> discussions have spawned half a decade from intellectual conception to
>>> activation in average (at least for segwit, schnorr, taproot).
>>>
>>> Such effort was a speak-by-the-act answer to the issues in
>>> consensus development changes pointed out by Jeremy Rubin in April of last
>>> year [1]: namely the lack of a "codified checklist" for consensus changes,
>>> that "consensus is memoryless" and "bitcoin core is not bitcoin"
>>> (independently of the technical concerns as I have as limited or
>>> non-adequate primitive for vaults / payment pools I expressed during the
>>> same time). Other complementary initiatives have been undertaken during the
>>> same period, AJ with the bitcoin-inquisition fork where the community of
>>> developers and contracting primitives of researchers on a consensus-enabled
>>> fork of core [2]. And Dave Harding with the careful archiving of all
>>> covenant proposals under the Optech umbrella [3].
>>>
>>> About the Bitcoin Contracting Primitives WG, a Github repository was
>>> started and maintained to archive and document all the primitives (apo,
>>> tluv, ctv, the taproot annex, sighash_group, CSFS, cat, txhash, evict,
>>> check_output_covenant_verify, inherited ids, anyamount, singletons,
>>> op_vault) and the corresponding protocols (payment pools, vaults,
>>> drivechains, trust-minimized mining pools payouts). We had a total of 6
>>> monthly meetings on the Libera chat #bitcoin-contracting-primitives-wg for
>>> a number of more than 20 individual attendees representing most of the
>>> parts of the community. I think (missing march logs). Numerous in-depth
>>> discussions did happen on the repository and on the channel on things like
>>> "merkelized all the things" or "payment pools for miners payoffs".
>>>
>>> As I've been busy on the Lightning-side and other Bitcoin projects, I've
>>> not run an online meeting since the month of April, while still having a
>>> bunch of fruitful technical discussions with folks involved in the effort
>>> at conferences and elsewhere. I launched the effort as an experiment with
>>> the soft commitment to dedicate 20% of my time on it, after few successful
>>> sessions I think such a process has an interest of its own, however it
>>> comes with direct competition of my time to work on Lightning robustness.
>>> Getting my hands dirty on low-level LDK development recently made me
>>> realize we still have years of titan work to get a secure and reliable
>>> Lightning Network.
>>>
>>> As such, between extended covenant capabilities for advanced contracts
>>> coming as a reality for Bitcoin _or_ LN working smoothly at scale with
>>> 50-100M UTXO-sharing users on it during the next 5-7 years cycle, I think
>>> the latter goal is more critical for Bitcoin existential survival, and
>>> where on a personal title I'll allocate the best of my time and energy (and
>>> somehow it match the "slow" technical activity on bitcoin-inquisition
>>> mostly done by Lightning hands).
>>>
>>> This is my personal conclusion only on the state of Bitcoin
>>> technological momentum, and this is quite tainted by my deep background in
>>> Lightning development. If you've been working on covenant changes
>>> proposals, please don't take it as a discouragement, I think Taproot
>>> (privacy-preserving script policies behind the taproot tree branches) and
>>> Schnorr (for native multi-sig) soft forks have shown how it can improve the
>>> building of self-custody solutions by one or two order of magnitude, and
>>> small incremental changes might be good enough to have a lower technical
>>> consensus bar.
>>>
>>> On my side, I'll pursue pure R&D works on CoinPool, notably coming with
>>> better solutions with the interactivity issue and mass-compression of
>>> withdrawal and design exotic advanced Bitcoin contracts based on the
>>> taproot annex, though more in a "l'art pour l'art" approach for the time
>>> being [4]. Additionally, I might start to submit an in-depth security
>>> review of consensus changes under pseudonyms, it has already been done in
>>> the past and somehow it's good practice in terms of "message neutrality"
>>> [5]. If folks wanna experiment in terms of payment pools deployment, Greg
>>> Maxwell's old joinpool can be used today (and somehow it's worthy of its
>>> own as a net advance for coinjoins).
>>>
>>> I'll honestly acknowledge towards the community, I might have
>>> overpromised with the kickstart of this new process aiming to move the
>>> frontlines in matters of Bitcoin consensus changes development process. On
>>> the other hand, I think enough sessions of the working group have been
>>> runned and enough marks of technical interests have been collected to
>>> demonstrate the minimal value of such a process, so I would estimate my
>>> open-source balance sheet towards the community to be in good standing ?
>>> (open-minded question).
>>>
>>> I don't think Bitcoin fundamentally lacks compelling technical proposals
>>> to advance the capabilities of Bitcoin Script today, nor the crowd of
>>> seasoned and smart protocol developers to evaluate mature proposals
>>> end-to-end and on multiple dimensions with a spirit of independence.
>>> Rather, I believe what Bitcoin is lacking is a small crowd of technical
>>> historians and archivist doing the work of assessing, collecting and
>>> preserving consensus changes proposals and QA devs to ensure any consensus
>>> change proposals has world-class battle-ground testing before to be
>>> considered for deployment, ideally with the best standards of Bitcoin
>>> decentralization and FOSS neutrality [6].
>>>
>>> If you would like to pursue the maintenance and nurturing of the Bitcoin
>>> Contracting Primitives WG (or the bitcoin-inquisition fork or collaborate
>>> with Optech to organize industry-wise workshop on covenants at the image of
>>> what has been done in 2019 for Taproot), that you're willing to show
>>> proof-of-work and you estimate that operational ground, legal information
>>> or financial resources will anchor your individual work on the long-term,
>>> don't hesitate to reach out, I'll see what I can do with a disinterested
>>> mind [7].
>>>
>>> With humility,
>>> Antoine
>>>
>>> [0]
>>> https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2022-July/020763.html
>>> [1]
>>> https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2022-April/020233.html
>>> [2]
>>> https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2022-September/020921.html
>>> [3] https://github.com/bitcoinops/bitcoinops.github.io/pull/806
>>> [4] Version 0.2 of the CoinPool whitepaper addressing most of the
>>> remaining "Big Problems" is still pending on my visit to co-author Gleb
>>> Naumenko in Ukraine, which has been postponed few times in light of the
>>> conflict operational evolutions.
>>> [5] See
>>> https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2020-February/017614.html.
>>> For the philosophical reasons of doing so, I invite you to read Foucault's
>>> famous essay "Le philosophe masque".
>>> [6] Somehow I come to share Jeremy's thesis's "Product management is not
>>> "my Job" it's yours" in matters of consensus changes. I believe we might be
>>> past the technical complexity threshold where even simple consensus changes
>>> can be conducted from A to Z as a one man job or even by a group of 2/3
>>> elite devs.
>>> [7] I've been reached out multiple times and consistently by R&D
>>> non-profits, plebs whales and VC firms who were interested to commit
>>> resources to advance softforks and covenants in the Bitcoin space, no doubt
>>> when you're reliable and with a track record, folks are ready to offer you
>>> opportunities to work full-time on consensus changes.
>>> _______________________________________________
>>> bitcoin-dev mailing list
>>> [email-masked]
>>> https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev
>>>
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