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Date: Tue, 14 Jan 2025 06:14:37 -0800 (PST)
From: /dev /fd0 <alicexbtong@gmail.com>
To: Bitcoin Development Mailing List <bitcoindev@googlegroups.com>
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Subject: Re: [bitcoindev] Summary: Covenants Support - Bitcoin Wiki
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We have been discussing the objections shared by Jonas Nick in his=20
rationale:=20
https://gist.github.com/jonasnick/e9627f56d04732ca83e94d448d4b5a51
Feel free to comment if you'd like to add something.
/dev/fd0
floppy disk guy
On Friday, January 3, 2025 at 5:45:29=E2=80=AFPM UTC+5:30 moonsettler wrote=
:
> Hi FLoppy,
>
> Of course I appreciate thoughtful evaluations.
>
> But my point stands, I encourage everyone to look at this table as means=
=20
> to engage in discussion not some indicator of "consensus" by any means.
>
> And I emphasized this, because there was a weird perception emerging, and=
=20
> even your own summary had this feel to it.
>
> BR,
> moonsettler
>
>
> Sent with Proton Mail secure email.
>
> On Thursday, January 2nd, 2025 at 4:16 PM, /dev /fd0 <alice...@gmail.com>=
=20
> wrote:
>
> > Hi moonsettler,
> > > Neither INTERNALKEY nor PAIRCOMMIT enables LN-Symmetry, LNhance does.=
=20
> They make it more efficient, and they also help other contracts.
> > Among them: Resumeable LN channels, Multi-party LN channels, Vaults, et=
c.
> >=20
> > I am aware of this and have used the comparison table in my=20
> [rationale][1]. LNHANCE is not an opcode. CTV and CSFS enable LN SYMMETRY=
.
> >=20
> > > Calling it "unnecessary complexity" is not a valid technical=20
> observation in any shape or form. It would provide optimization for many=
=20
> contracts and use cases even if we had CAT. I explained this to you in=20
> private first, yet you keep insisting on this completely invalid objectio=
n.
> >=20
> > It is a valid objection and I find it disappointing that you think=20
> people will change their opinion about an opcode if you build [activation=
=20
> client][2] or a different table. If you read all the rationales, its not=
=20
> just me who finds this opcode irrelevant. Please respect the developers w=
ho=20
> shared their evaluations in the table even if you disagree with them. If=
=20
> you cannot appreciate efforts to review proposals and reach technical=20
> consensus, at least avoid calling reviews/evaluations as "voting".
> >=20
> > "Unnecessary" because LN symmetry (efficient) is possible without it.=
=20
> "Complexity" is introduced because it will be used for everything possibl=
e=20
> with it in bitcoin script and not just the use cases described in your=20
> email.
> >=20
> > /dev/fd0
> > floppy disk guy
> >=20
> > [1]: https://gitlab.com/-/snippets/4777553
> > [2]: https://groups.google.com/g/bitcoindev/c/QOnpM4Ixmms/m/eodYc71lDAA=
J
> > On Thursday, January 2, 2025 at 7:16:55=E2=80=AFPM UTC+5:30 moonsettler=
wrote:
> >=20
> > > Hi Floppy,
> > >=20
> > > Neither INTERNALKEY nor PAIRCOMMIT enables LN-Symmetry, LNhance does.=
=20
> They make it more efficient, and they also help other contracts.
> > > Among them: Resumeable LN channels, Multi-party LN channels, Vaults,=
=20
> etc.
> > >=20
> > > Main benefit for the network: we can reduce the number of SigOps=20
> on-chain which benefits everyone that runs a validating node by making it=
=20
> more economic to use a single signature for multiple elements instead of=
=20
> using something like the ReKey technique.
> > >=20
> > > Calling it "unnecessary complexity" is not a valid technical=20
> observation in any shape or form. It would provide optimization for many=
=20
> contracts and use cases even if we had CAT. I explained this to you in=20
> private first, yet you keep insisting on this completely invalid objectio=
n.
> > >=20
> > > BR,
> > > moonsettler
> > >=20
> > > PS: I largely agree with everything Ethan said.
> > >=20
> > > Sent with Proton Mail secure email.
> > >=20
> > > On Thursday, January 2nd, 2025 at 2:22 AM, /dev /fd0 <
> alice...@gmail.com> wrote:
> > >=20
> > > > Hi Ethan,
> > > > OP_CAT is not proposed as an opcode to enable LN SYMMETRY. Whereas=
=20
> OP_PAIRCOMMIT is a part of LNHANCE.
> > > >
> > > > In this context, OP_PAIRCOMMIT adds unnecessary complexity because=
=20
> LN SYMMETRY can be achieved with other opcodes.
> > > >
> > > > Note: The objections shared in this thread are a summarised version=
=20
> of all the rationales and not my person opinion.
> > > >
> > > > /dev/fd0
> > > > floppy disk guy
> > > >
> > > > On Wed, Jan 1, 2025, 11:49 PM Ethan Heilman <eth...@gmail.com>=20
> wrote:
> > > >
> > > > > One of the CAT authors here
> > > > >
> > > > > > > [PAIR_COMMIT] Adds unnecessary complexity
> > > > > > That's a subjective value judgement it enables something that=
=20
> was no possible before which is interacting with Merkle trees and=20
> multi-element commitments in script. PAIRCOMMIT is not significantly more=
=20
> complicated than CAT, and in a lot of actual use cases CAT was desired fo=
r=20
> it's more complex and resource intensive to safely use CAT than PAIRCOMMI=
T=20
> due to witness malleability.
> > > > >
> > > > > PAIR_COMMIT (BIP-442) for all intents and purposes is as simple i=
n
> > > > > implementation at CAT (BIP-347). I have no technical objection to
> > > > > PAIRCOMMIT and it provides much needed functionality.
> > > > >
> > > > > My primary concern is not PAIRCOMMIT itself, but the rationale fo=
r=20
> PAIRCOMMIT.
> > > > >
> > > > > The rationale for PAIRCOMMIT rests on the assumption that the=20
> Bitcoin
> > > > > community does not want the expressiveness of CAT. If we assume=
=20
> this
> > > > > is the case, then we should be very careful PAIRCOMMIT does not=
=20
> enable
> > > > > this expressiveness as well. On the other hand, if the Bitcoin
> > > > > community does want the expressiveness of CAT, then we should mer=
ge
> > > > > CAT. PAIRCOMMIT is well designed to be less expressive than CAT=
=20
> and it
> > > > > is likely that you can not simulate CAT with PAIRCOMMIT. That=20
> said, I
> > > > > am not convinced it is impossible that there is no way to simulat=
e=20
> CAT
> > > > > with PAIRCOMMIT, nor I do feel confident that I know how much les=
s
> > > > > powerful PAIRCOMMIT is than CAT.
> > > > >
> > > > > Playing devil's advocate for a second, if I was opposed to CAT on
> > > > > grounds that we should limit expressiveness I would want to reall=
y
> > > > > understand the limits of PAIRCOMMIT. For instance can you do=20
> arbitrary
> > > > > computation by building STARKs with PAIRCOMMIT merkle trees? If=
=20
> not,
> > > > > why not?
> > > > >
> > > > > That said, I have not heard any argument against PAIRCOMMIT from=
=20
> those
> > > > > against CAT, so perhaps they are comfortable with it.
> > > > >
> > > > > Since I am in favor of CAT, I am also in favor of PAIRCOMMIT.
> > > > >
> > > > > On Tue, Dec 31, 2024 at 9:23=E2=80=AFAM 'moonsettler' via Bitcoin=
=20
> Development
> > > > > Mailing List <bitco...@googlegroups.com> wrote:
> > > > > >
> > > > > > Hi All,
> > > > > >
> > > > > > One thing I would like to make clear before people get the wron=
g=20
> idea and think this is some form of voting, OP_INTERNALKEY and OP_PARCOMM=
IT=20
> is part of LNhance and will be part of the activation client we release=
=20
> soon. The only way to change that is to demonstrate actual harm. You liki=
ng=20
> something else more, is your problem. What you can do about it, is write=
=20
> your activation client and try to gain consensus on that. There are plent=
y=20
> of version bits available. Replacing PAIRCOMMIT with CAT would be really=
=20
> easy, but while CAT is indeed very popular and has a wide support base it=
=20
> is also strongly opposed by many who did not choose to participate. I'm n=
ot=20
> convinced that this table represents actual developer, let alone ecosyste=
m=20
> consensus. If you decide you want to run an alternative activation effort=
=20
> with CAT instead of PAIRCOMMIT feel free to fork our repo!
> > > > > >
> > > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D
> > > > > > OP_PARCOMMIT
> > > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D
> > > > > >
> > > > > > > OP_PARCOMMIT seems to be controversial at this moment.
> > > > > >
> > > > > > I strongly disagree. In my book that's not what controversial=
=20
> means. Literally nobody managed to come up with a single use case anyone=
=20
> worth noting objects to for PAIRCOMMIT. Also inclined to ignore the "No"=
=20
> from those that prefer CAT as plain trolling. This BIP is young, there is=
a=20
> clear correlation between the age of the proposals and their support with=
=20
> the sole exception of APO.
> > > > > >
> > > > > > > Adds unnecessary complexity
> > > > > >
> > > > > > That's a subjective value judgement it enables something that=
=20
> was no possible before which is interacting with Merkle trees and=20
> multi-element commitments in script. PAIRCOMMIT is not significantly more=
=20
> complicated than CAT, and in a lot of actual use cases CAT was desired fo=
r=20
> it's more complex and resource intensive to safely use CAT than PAIRCOMMI=
T=20
> due to witness malleability.
> > > > > >
> > > > > > > Not convinced it is impossible that there is no way to=20
> simulate CAT with PAIRCOMMIT, nor confident how much less powerful=20
> PAIRCOMMIT is than CAT.
> > > > > >
> > > > > > This is sufficiently addressed in the BIP.
> > > > > >
> > > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D
> > > > > > OP_VAULT
> > > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D
> > > > > >
> > > > > > > No demand for vaults.
> > > > > >
> > > > > > It's safe to completely ignore that "argument".
> > > > > >
> > > > > > BR,
> > > > > > moonsettler
> > > > > >
> > > > > >
> > > > > > On Tuesday, December 31st, 2024 at 9:23 AM, /dev /fd0 <
> alice...@gmail.com> wrote:
> > > > > >
> > > > > > > Hi Bitcoin Developers,
> > > > > > >
> > > > > > > I had shared covenants support wiki page link here on [mailin=
g=20
> list][1] in the last week of November 2024. Multiple changes were made=20
> based on the feedback:
> > > > > > >
> > > > > > > - Removed 'community support' from 'No'. Rephrased definition=
s=20
> for 'Prefer' and 'Evaluating'.
> > > > > > > - Added LNHANCE category for a combination of opcodes.
> > > > > > > - Added links for BIP drafts and a column for 'rationale'.
> > > > > > > - Created a separate table for evaluations without a rational=
e.
> > > > > > >
> > > > > > > Murch and Gloria shared their feedback in the bitcoin optech=
=20
> [podcast 333][2]. I have started working on a [page][3] that lists use=20
> cases, prototype links and primitives used. We can still add more use cas=
es=20
> in it. This list does not include use cases enabled by=20
> [OP_CHECKSIGFROMSTACK][4] alone or in combination with other opcodes like=
=20
> [LN SYMMETRY][5].
> > > > > > >
> > > > > > > I had verified each entry to avoid spam and fake evaluations.=
=20
> Rearden was assigned moderator permissions on 8 December 2024 by Theymos =
to=20
> help me with the moderations. Some edits have been approved by other=20
> moderators.
> > > > > > >
> > > > > > > Some insights from the table that could help developers=20
> working on different covenant proposals:
> > > > > > >
> > > > > > > 1. Multiple ways to achieve LN symmetry were discovered.=20
> SIGHASH_APO lacks interest among developers, contrary to the belief prior=
=20
> to this exercise.
> > > > > > > 2. OP_CHECKSIGFROMSTACK has unanimous support and is a part o=
f=20
> multiple covenant proposals.
> > > > > > > 3. OP_PAIRCOMMIT, OP_INTERNALKEY and OP_CHECKCONTRACTVERIFY=
=20
> are not reviewed by enough developers. OP_PARCOMMIT seems to be=20
> controversial at this moment.
> > > > > > >
> > > > > > > Objections:
> > > > > > >
> > > > > > > ```
> > > > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D
> > > > > > > SIGHASH_APO
> > > > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D
> > > > > > >
> > > > > > > LN SYMMETRY is possible with combination of a few opcodes=20
> which is more efficient. Its not the best option for covenants and cannot=
=20
> be used to improve Ark. Some developers prefer opcodes and not sighash=20
> flags.
> > > > > > >
> > > > > > > Seems to be the result of an attempt to fix signatures to mak=
e=20
> them work for a specific use-case, but the end-result is hard-to-reason=
=20
> (for me) and not flexible. In general, SIGHASH flags are an encoding of=
=20
> specific predicates on the transaction, and I think the Script is better=
=20
> suited to carry the predicate. There is no interesting SIGHASH flag that=
=20
> couldn't be functionally simulated by introspection + CHECKSIGFROMSTACK (=
or=20
> other Script-based approaches), and that seems to me a much cleaner and=
=20
> ergonomic way to achieve the same goals.
> > > > > > >
> > > > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D
> > > > > > > OP_TXHASH
> > > > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D
> > > > > > >
> > > > > > > More expressive, many flag configurations, untested and=20
> undesirable use cases. Unaddressed comments in the BIP and the delay=20
> doesn't make sense because OP_CHECKTEMPLATEVERIFY can be upgraded later t=
o=20
> achieve the same thing. Makes hash caching complex, potentially opening u=
p=20
> DoS vectors or quadratic sighash.
> > > > > > >
> > > > > > > Most templates you'd obtain with various combinations of=20
> parameters are meaningless. It implements state-carrying UTXOs in a very=
=20
> dirty way: adding additional inputs/outputs with no other meaning than=20
> "storing some state". This is ugly, inefficient, and bloats the UTXO set =
-=20
> and it definitely will happen if TXHASH is enabled without also enabling =
a=20
> clean way to carry state.
> > > > > > >
> > > > > > > Follow up with an upgrade to OP_CHECKTEMPLATEVERIFY can fine=
=20
> tune it to what people are actually using covenants for, instead of=20
> prematurely optimizing everything with no data.
> > > > > > >
> > > > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D
> > > > > > > OP_VAULT
> > > > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D
> > > > > > >
> > > > > > > No demand for vaults. Customized for a specific use case.
> > > > > > >
> > > > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D
> > > > > > > OP_CAT
> > > > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D
> > > > > > >
> > > > > > > Can be used for various complex scripts including undesirable=
=20
> use cases (DEX, AMM and Hashrate Escrow). Enables granular transaction=20
> introspection through abuse of schnorr signatures and OP_CHECKSIG. Can be=
=20
> used for interesting use cases but alone does it poorly and inefficiently=
.
> > > > > > >
> > > > > > > People can and will litter the chain with inefficient/ugly=20
> Scripts if activated alone. Since it happens to enable generic=20
> introspection by accident, and therefore an ugly version of state-carryin=
g=20
> UTXOs, it shouldn't be enabled without more ergonomic opcodes for those u=
se=20
> cases.
> > > > > > >
> > > > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D
> > > > > > > OP_INTERNALKEY
> > > > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D
> > > > > > >
> > > > > > > There are 3 'No' in the table, I couldn't find anything=20
> relevant in the rationales.
> > > > > > >
> > > > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D
> > > > > > > OP_PAIRCOMMIT
> > > > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D
> > > > > > >
> > > > > > > Adds unnecessary complexity, redundant if OP_CAT is activated=
=20
> in future and added for specific use case. LN SYMMETRY is possible withou=
t=20
> this opcode. It does not compose with anything that involves transaction=
=20
> introspection due to its specified tagged hash. Some developers prefer=20
> OP_CAT.
> > > > > > >
> > > > > > > Not convinced it is impossible that there is no way to=20
> simulate CAT with PAIRCOMMIT, nor confident how much less powerful=20
> PAIRCOMMIT is than CAT.
> > > > > > >
> > > > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D
> > > > > > > OP_CHECKTEMPLATEVERIFY
> > > > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D
> > > > > > >
> > > > > > > Limited in scope and not recursive.
> > > > > > > ```
> > > > > > >
> > > > > > > I have tried my best to remain unbiased in writing this=20
> summary and approving edits. There are a few things that I want to share=
=20
> and it could be a result of the aggressive marketing:
> > > > > > >
> > > > > > > - A spammer had edited the table to remove all evaluations=20
> except in favor of OP_CAT and it was rejected.
> > > > > > > - [Rationale][6] added by Aaron (sCrypt) does not mention=20
> anything about other opcodes and SIGHASH_APO. It is only focused on OP_CA=
T=20
> however evaluations exist in the table.
> > > > > > > - I [requested][7] Udev (CatSwap) to add details about=20
> evaluation of other opcodes and SIGHASH_APO.
> > > > > > > - Last [edit][8] by Roujiamo (bitdollar) has a rationale with=
=20
> incorrect signet stats and seems to be rephrased version of another=20
> rationale. Evaluation had 'weak' for OP_CTV before adding the rationale.
> > > > > > > - An edit with duplicate rationale (in support of OP_CAT) was=
=20
> rejected because sharing the link for a rationale submitted by other=20
> developer adds no value in the table.
> > > > > > >
> > > > > > > Evaluations without a rationale have some 'No' in different=
=20
> cells. Although none of them are backed by a rationale so cannot be=20
> considered for consensus discussion. The table is still updated regularly=
=20
> so you may see some of them with a rationale in 2025. Any suggestions to=
=20
> help achieve technical consensus are most welcome.
> > > > > > >
> > > > > > > What's next?
> > > > > > >
> > > > > > > - More rationales in the table
> > > > > > > - Discuss objections on mailing list (if any)
> > > > > > > - Workshops
> > > > > > > - Add a table for economic nodes and their opinion
> > > > > > > - Build activation client and discuss parameters
> > > > > > >
> > > > > > > Finally, I would thank all the developers who added their=20
> evaluations in the table and everyone who shared updates on twitter. It w=
as=20
> a coordinated effort to reach some technical consensus. You can read all=
=20
> the rationales in detail to understand different perspectives and reasons=
=20
> to support a combination of opcodes over others.
> > > > > > >
> > > > > > > [1]:=20
> https://groups.google.com/g/bitcoindev/c/fdxkE1Al4TI/m/CeEuls2IAQAJ
> > > > > > > [2]: https://bitcoinops.org/en/podcast/2024/12/17/
> > > > > > > [3]: https://en.bitcoin.it/wiki/Covenants_Uses
> > > > > > > [4]: https://github.com/bitcoin/bips/blob/master/bip-0348.md
> > > > > > > [5]:=20
> https://gist.github.com/Ademan/4a14614fa850511d63a5b2a9b5104cb7
> > > > > > > [6]:=20
> https://gist.github.com/gitzhou/dc92c41db1987db16fe665c26bc56dd9
> > > > > > > [7]:=20
> https://gist.github.com/udevswap/b768d20d62549922b9e72428ef9eb608?permali=
nk_comment_id=3D5359072#gistcomment-5359072
> > > > > > > [8]:=20
> https://en.bitcoin.it/w/index.php?title=3DCovenants_support&diff=3Dprev&o=
ldid=3D70520
> > > > > > >
> > > > > > > /dev/fd0
> > > > > > > floppy disk guy
> > > > > > >
> > > > > > > --
> > > > > > > You received this message because you are subscribed to the=
=20
> Google Groups "Bitcoin Development Mailing List" group.
> > > > > > > To unsubscribe from this group and stop receiving emails from=
=20
> it, send an email to bitcoindev+...@googlegroups.com.
> > > > > > > To view this discussion visit=20
> https://groups.google.com/d/msgid/bitcoindev/38a6f252-afe9-4155-a341-11a4=
2a9a9007n%40googlegroups.com
> .
> > > > > >
> > > > > > --
> > > > > > You received this message because you are subscribed to the=20
> Google Groups "Bitcoin Development Mailing List" group.
> > > > > > To unsubscribe from this group and stop receiving emails from=
=20
> it, send an email to bitcoindev+...@googlegroups.com.
> > > > > > To view this discussion visit=20
> https://groups.google.com/d/msgid/bitcoindev/rp07_AsZrGYA3kFwZweIhzZVonmc=
uQktAz9r51MgKvrG101_T9NBTTMCFK_q3bMzIH0-QzfFtzC6uJGEKOIMi6Hl6qwbDtMWXXV2frB=
WXac%3D%40protonmail.com
> .
> > > > >
> > > > > --
> > > > > You received this message because you are subscribed to the Googl=
e=20
> Groups "Bitcoin Development Mailing List" group.
> > > > > To unsubscribe from this group and stop receiving emails from it,=
=20
> send an email to bitcoindev+...@googlegroups.com.
> > > > > To view this discussion visit=20
> https://groups.google.com/d/msgid/bitcoindev/CAEM%3Dy%2BV9Gu0n7pLv1d%2BK1=
HfaFsB3kXg-LbtppyZG0xjAa7DBaA%40mail.gmail.com
> .
> >=20
> > --
> > You received this message because you are subscribed to the Google=20
> Groups "Bitcoin Development Mailing List" group.
> > To unsubscribe from this group and stop receiving emails from it, send=
=20
> an email to bitcoindev+...@googlegroups.com.
> > To view this discussion visit=20
> https://groups.google.com/d/msgid/bitcoindev/c411dee9-1937-42fd-bc66-d347=
ddbff506n%40googlegroups.com
> .
>
--=20
You received this message because you are subscribed to the Google Groups "=
Bitcoin Development Mailing List" group.
To unsubscribe from this group and stop receiving emails from it, send an e=
mail to bitcoindev+unsubscribe@googlegroups.com.
To view this discussion visit https://groups.google.com/d/msgid/bitcoindev/=
c7486012-79a3-46e4-a310-a3d0edb47e97n%40googlegroups.com.
------=_Part_534799_1161673789.1736864077681
Content-Type: text/html; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
We have been discussing the objections shared by Jonas Nick in his rational=
e: <a href=3D"https://gist.github.com/jonasnick/e9627f56d04732ca83e94d448d4=
b5a51">https://gist.github.com/jonasnick/e9627f56d04732ca83e94d448d4b5a51</=
a><br /><br />Feel free to comment if you'd like to add something.<br /><di=
v><br /></div><div>/dev/fd0</div><div>floppy disk guy<br /><br /></div><div=
class=3D"gmail_quote"><div dir=3D"auto" class=3D"gmail_attr">On Friday, Ja=
nuary 3, 2025 at 5:45:29=E2=80=AFPM UTC+5:30 moonsettler wrote:<br/></div><=
blockquote class=3D"gmail_quote" style=3D"margin: 0 0 0 0.8ex; border-left:=
1px solid rgb(204, 204, 204); padding-left: 1ex;">Hi FLoppy,
<br>
<br>Of course I appreciate thoughtful evaluations.
<br>
<br>But my point stands, I encourage everyone to look at this table as mean=
s to engage in discussion not some indicator of "consensus" by an=
y means.
<br>
<br>And I emphasized this, because there was a weird perception emerging, a=
nd even your own summary had this feel to it.
<br>
<br>BR,
<br>moonsettler
<br>
<br>
<br>Sent with Proton Mail secure email.
<br>
<br>On Thursday, January 2nd, 2025 at 4:16 PM, /dev /fd0 <<a href data-e=
mail-masked rel=3D"nofollow">alice...@gmail.com</a>> wrote:
<br>
<br>> Hi moonsettler,
<br>> > Neither INTERNALKEY nor PAIRCOMMIT enables LN-Symmetry, LNhan=
ce does. They make it more efficient, and they also help other contracts.
<br>> Among them: Resumeable LN channels, Multi-party LN channels, Vault=
s, etc.
<br>>=20
<br>> I am aware of this and have used the comparison table in my [ratio=
nale][1]. LNHANCE is not an opcode. CTV and CSFS enable LN SYMMETRY.
<br>>=20
<br>> > Calling it "unnecessary complexity" is not a valid =
technical observation in any shape or form. It would provide optimization f=
or many contracts and use cases even if we had CAT. I explained this to you=
in private first, yet you keep insisting on this completely invalid object=
ion.
<br>>=20
<br>> It is a valid objection and I find it disappointing that you think=
people will change their opinion about an opcode if you build [activation =
client][2] or a different table. If you read all the rationales, its not ju=
st me who finds this opcode irrelevant. Please respect the developers who s=
hared their evaluations in the table even if you disagree with them. If you=
cannot appreciate efforts to review proposals and reach technical consensu=
s, at least avoid calling reviews/evaluations as "voting".
<br>>=20
<br>> "Unnecessary" because LN symmetry (efficient) is possibl=
e without it. "Complexity" is introduced because it will be used =
for everything possible with it in bitcoin script and not just the use case=
s described in your email.
<br>>=20
<br>> /dev/fd0
<br>> floppy disk guy
<br>>=20
<br>> [1]: <a href=3D"https://gitlab.com/-/snippets/4777553" target=3D"_=
blank" rel=3D"nofollow" data-saferedirecturl=3D"https://www.google.com/url?=
hl=3Den&q=3Dhttps://gitlab.com/-/snippets/4777553&source=3Dgmail&am=
p;ust=3D1736950171965000&usg=3DAOvVaw0HSElHlm4jTJOjUcAcUNBy">https://gi=
tlab.com/-/snippets/4777553</a>
<br>> [2]: <a href=3D"https://groups.google.com/g/bitcoindev/c/QOnpM4Ixm=
ms/m/eodYc71lDAAJ" target=3D"_blank" rel=3D"nofollow" data-saferedirecturl=
=3D"https://www.google.com/url?hl=3Den&q=3Dhttps://groups.google.com/g/=
bitcoindev/c/QOnpM4Ixmms/m/eodYc71lDAAJ&source=3Dgmail&ust=3D173695=
0171965000&usg=3DAOvVaw176WiEe9X8xwddafZbZuAx">https://groups.google.co=
m/g/bitcoindev/c/QOnpM4Ixmms/m/eodYc71lDAAJ</a>
<br>> On Thursday, January 2, 2025 at 7:16:55=E2=80=AFPM UTC+5:30 moonse=
ttler wrote:
<br>>=20
<br>> > Hi Floppy,
<br>> >=20
<br>> > Neither INTERNALKEY nor PAIRCOMMIT enables LN-Symmetry, LNhan=
ce does. They make it more efficient, and they also help other contracts.
<br>> > Among them: Resumeable LN channels, Multi-party LN channels, =
Vaults, etc.
<br>> >=20
<br>> > Main benefit for the network: we can reduce the number of Sig=
Ops on-chain which benefits everyone that runs a validating node by making =
it more economic to use a single signature for multiple elements instead of=
using something like the ReKey technique.
<br>> >=20
<br>> > Calling it "unnecessary complexity" is not a valid =
technical observation in any shape or form. It would provide optimization f=
or many contracts and use cases even if we had CAT. I explained this to you=
in private first, yet you keep insisting on this completely invalid object=
ion.
<br>> >=20
<br>> > BR,
<br>> > moonsettler
<br>> >=20
<br>> > PS: I largely agree with everything Ethan said.
<br>> >=20
<br>> > Sent with Proton Mail secure email.
<br>> >=20
<br>> > On Thursday, January 2nd, 2025 at 2:22 AM, /dev /fd0 <<a h=
ref data-email-masked rel=3D"nofollow">alice...@gmail.com</a>> wrote:
<br>> >=20
<br>> > > Hi Ethan,
<br>> > > OP_CAT is not proposed as an opcode to enable LN SYMMETR=
Y. Whereas OP_PAIRCOMMIT is a part of LNHANCE.
<br>> > >
<br>> > > In this context, OP_PAIRCOMMIT adds unnecessary complexi=
ty because LN SYMMETRY can be achieved with other opcodes.
<br>> > >
<br>> > > Note: The objections shared in this thread are a summari=
sed version of all the rationales and not my person opinion.
<br>> > >
<br>> > > /dev/fd0
<br>> > > floppy disk guy
<br>> > >
<br>> > > On Wed, Jan 1, 2025, 11:49 PM Ethan Heilman <<a href =
data-email-masked rel=3D"nofollow">eth...@gmail.com</a>> wrote:
<br>> > >
<br>> > > > One of the CAT authors here
<br>> > > >
<br>> > > > > > [PAIR_COMMIT] Adds unnecessary complexity
<br>> > > > > That's a subjective value judgement it ena=
bles something that was no possible before which is interacting with Merkle=
trees and multi-element commitments in script. PAIRCOMMIT is not significa=
ntly more complicated than CAT, and in a lot of actual use cases CAT was de=
sired for it's more complex and resource intensive to safely use CAT th=
an PAIRCOMMIT due to witness malleability.
<br>> > > >
<br>> > > > PAIR_COMMIT (BIP-442) for all intents and purposes =
is as simple in
<br>> > > > implementation at CAT (BIP-347). I have no technica=
l objection to
<br>> > > > PAIRCOMMIT and it provides much needed functionalit=
y.
<br>> > > >
<br>> > > > My primary concern is not PAIRCOMMIT itself, but th=
e rationale for PAIRCOMMIT.
<br>> > > >
<br>> > > > The rationale for PAIRCOMMIT rests on the assumptio=
n that the Bitcoin
<br>> > > > community does not want the expressiveness of CAT. =
If we assume this
<br>> > > > is the case, then we should be very careful PAIRCOM=
MIT does not enable
<br>> > > > this expressiveness as well. On the other hand, if =
the Bitcoin
<br>> > > > community does want the expressiveness of CAT, then=
we should merge
<br>> > > > CAT. PAIRCOMMIT is well designed to be less express=
ive than CAT and it
<br>> > > > is likely that you can not simulate CAT with PAIRCO=
MMIT. That said, I
<br>> > > > am not convinced it is impossible that there is no =
way to simulate CAT
<br>> > > > with PAIRCOMMIT, nor I do feel confident that I kno=
w how much less
<br>> > > > powerful PAIRCOMMIT is than CAT.
<br>> > > >
<br>> > > > Playing devil's advocate for a second, if I was=
opposed to CAT on
<br>> > > > grounds that we should limit expressiveness I would=
want to really
<br>> > > > understand the limits of PAIRCOMMIT. For instance c=
an you do arbitrary
<br>> > > > computation by building STARKs with PAIRCOMMIT merk=
le trees? If not,
<br>> > > > why not?
<br>> > > >
<br>> > > > That said, I have not heard any argument against PA=
IRCOMMIT from those
<br>> > > > against CAT, so perhaps they are comfortable with i=
t.
<br>> > > >
<br>> > > > Since I am in favor of CAT, I am also in favor of P=
AIRCOMMIT.
<br>> > > >
<br>> > > > On Tue, Dec 31, 2024 at 9:23=E2=80=AFAM 'moonse=
ttler' via Bitcoin Development
<br>> > > > Mailing List <<a href data-email-masked rel=3D"n=
ofollow">bitco...@googlegroups.com</a>> wrote:
<br>> > > > >
<br>> > > > > Hi All,
<br>> > > > >
<br>> > > > > One thing I would like to make clear before pe=
ople get the wrong idea and think this is some form of voting, OP_INTERNALK=
EY and OP_PARCOMMIT is part of LNhance and will be part of the activation c=
lient we release soon. The only way to change that is to demonstrate actual=
harm. You liking something else more, is your problem. What you can do abo=
ut it, is write your activation client and try to gain consensus on that. T=
here are plenty of version bits available. Replacing PAIRCOMMIT with CAT wo=
uld be really easy, but while CAT is indeed very popular and has a wide sup=
port base it is also strongly opposed by many who did not choose to partici=
pate. I'm not convinced that this table represents actual developer, le=
t alone ecosystem consensus. If you decide you want to run an alternative a=
ctivation effort with CAT instead of PAIRCOMMIT feel free to fork our repo!
<br>> > > > >
<br>> > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D
<br>> > > > > OP_PARCOMMIT
<br>> > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D
<br>> > > > >
<br>> > > > > > OP_PARCOMMIT seems to be controversial at=
this moment.
<br>> > > > >
<br>> > > > > I strongly disagree. In my book that's not=
what controversial means. Literally nobody managed to come up with a singl=
e use case anyone worth noting objects to for PAIRCOMMIT. Also inclined to =
ignore the "No" from those that prefer CAT as plain trolling. Thi=
s BIP is young, there is a clear correlation between the age of the proposa=
ls and their support with the sole exception of APO.
<br>> > > > >
<br>> > > > > > Adds unnecessary complexity
<br>> > > > >
<br>> > > > > That's a subjective value judgement it ena=
bles something that was no possible before which is interacting with Merkle=
trees and multi-element commitments in script. PAIRCOMMIT is not significa=
ntly more complicated than CAT, and in a lot of actual use cases CAT was de=
sired for it's more complex and resource intensive to safely use CAT th=
an PAIRCOMMIT due to witness malleability.
<br>> > > > >
<br>> > > > > > Not convinced it is impossible that there=
is no way to simulate CAT with PAIRCOMMIT, nor confident how much less pow=
erful PAIRCOMMIT is than CAT.
<br>> > > > >
<br>> > > > > This is sufficiently addressed in the BIP.
<br>> > > > >
<br>> > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D
<br>> > > > > OP_VAULT
<br>> > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D
<br>> > > > >
<br>> > > > > > No demand for vaults.
<br>> > > > >
<br>> > > > > It's safe to completely ignore that "=
argument".
<br>> > > > >
<br>> > > > > BR,
<br>> > > > > moonsettler
<br>> > > > >
<br>> > > > >
<br>> > > > > On Tuesday, December 31st, 2024 at 9:23 AM, /d=
ev /fd0 <<a href data-email-masked rel=3D"nofollow">alice...@gmail.com</=
a>> wrote:
<br>> > > > >
<br>> > > > > > Hi Bitcoin Developers,
<br>> > > > > >
<br>> > > > > > I had shared covenants support wiki page =
link here on [mailing list][1] in the last week of November 2024. Multiple =
changes were made based on the feedback:
<br>> > > > > >
<br>> > > > > > - Removed 'community support' fro=
m 'No'. Rephrased definitions for 'Prefer' and 'Evaluat=
ing'.
<br>> > > > > > - Added LNHANCE category for a combinatio=
n of opcodes.
<br>> > > > > > - Added links for BIP drafts and a column=
for 'rationale'.
<br>> > > > > > - Created a separate table for evaluation=
s without a rationale.
<br>> > > > > >
<br>> > > > > > Murch and Gloria shared their feedback in=
the bitcoin optech [podcast 333][2]. I have started working on a [page][3]=
that lists use cases, prototype links and primitives used. We can still ad=
d more use cases in it. This list does not include use cases enabled by [OP=
_CHECKSIGFROMSTACK][4] alone or in combination with other opcodes like [LN =
SYMMETRY][5].
<br>> > > > > >
<br>> > > > > > I had verified each entry to avoid spam a=
nd fake evaluations. Rearden was assigned moderator permissions on 8 Decemb=
er 2024 by Theymos to help me with the moderations. Some edits have been ap=
proved by other moderators.
<br>> > > > > >
<br>> > > > > > Some insights from the table that could h=
elp developers working on different covenant proposals:
<br>> > > > > >
<br>> > > > > > 1. Multiple ways to achieve LN symmetry w=
ere discovered. SIGHASH_APO lacks interest among developers, contrary to th=
e belief prior to this exercise.
<br>> > > > > > 2. OP_CHECKSIGFROMSTACK has unanimous sup=
port and is a part of multiple covenant proposals.
<br>> > > > > > 3. OP_PAIRCOMMIT, OP_INTERNALKEY and OP_C=
HECKCONTRACTVERIFY are not reviewed by enough developers. OP_PARCOMMIT seem=
s to be controversial at this moment.
<br>> > > > > >
<br>> > > > > > Objections:
<br>> > > > > >
<br>> > > > > > ```
<br>> > > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D
<br>> > > > > > SIGHASH_APO
<br>> > > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D
<br>> > > > > >
<br>> > > > > > LN SYMMETRY is possible with combination =
of a few opcodes which is more efficient. Its not the best option for coven=
ants and cannot be used to improve Ark. Some developers prefer opcodes and =
not sighash flags.
<br>> > > > > >
<br>> > > > > > Seems to be the result of an attempt to f=
ix signatures to make them work for a specific use-case, but the end-result=
is hard-to-reason (for me) and not flexible. In general, SIGHASH flags are=
an encoding of specific predicates on the transaction, and I think the Scr=
ipt is better suited to carry the predicate. There is no interesting SIGHAS=
H flag that couldn't be functionally simulated by introspection + CHECK=
SIGFROMSTACK (or other Script-based approaches), and that seems to me a muc=
h cleaner and ergonomic way to achieve the same goals.
<br>> > > > > >
<br>> > > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D
<br>> > > > > > OP_TXHASH
<br>> > > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D
<br>> > > > > >
<br>> > > > > > More expressive, many flag configurations=
, untested and undesirable use cases. Unaddressed comments in the BIP and t=
he delay doesn't make sense because OP_CHECKTEMPLATEVERIFY can be upgra=
ded later to achieve the same thing. Makes hash caching complex, potentiall=
y opening up DoS vectors or quadratic sighash.
<br>> > > > > >
<br>> > > > > > Most templates you'd obtain with vari=
ous combinations of parameters are meaningless. It implements state-carryin=
g UTXOs in a very dirty way: adding additional inputs/outputs with no other=
meaning than "storing some state". This is ugly, inefficient, an=
d bloats the UTXO set - and it definitely will happen if TXHASH is enabled =
without also enabling a clean way to carry state.
<br>> > > > > >
<br>> > > > > > Follow up with an upgrade to OP_CHECKTEMP=
LATEVERIFY can fine tune it to what people are actually using covenants for=
, instead of prematurely optimizing everything with no data.
<br>> > > > > >
<br>> > > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D
<br>> > > > > > OP_VAULT
<br>> > > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D
<br>> > > > > >
<br>> > > > > > No demand for vaults. Customized for a sp=
ecific use case.
<br>> > > > > >
<br>> > > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D
<br>> > > > > > OP_CAT
<br>> > > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D
<br>> > > > > >
<br>> > > > > > Can be used for various complex scripts i=
ncluding undesirable use cases (DEX, AMM and Hashrate Escrow). Enables gran=
ular transaction introspection through abuse of schnorr signatures and OP_C=
HECKSIG. Can be used for interesting use cases but alone does it poorly and=
inefficiently.
<br>> > > > > >
<br>> > > > > > People can and will litter the chain with=
inefficient/ugly Scripts if activated alone. Since it happens to enable ge=
neric introspection by accident, and therefore an ugly version of state-car=
rying UTXOs, it shouldn't be enabled without more ergonomic opcodes for=
those use cases.
<br>> > > > > >
<br>> > > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D
<br>> > > > > > OP_INTERNALKEY
<br>> > > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D
<br>> > > > > >
<br>> > > > > > There are 3 'No' in the table, I =
couldn't find anything relevant in the rationales.
<br>> > > > > >
<br>> > > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D
<br>> > > > > > OP_PAIRCOMMIT
<br>> > > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D
<br>> > > > > >
<br>> > > > > > Adds unnecessary complexity, redundant if=
OP_CAT is activated in future and added for specific use case. LN SYMMETRY=
is possible without this opcode. It does not compose with anything that in=
volves transaction introspection due to its specified tagged hash. Some dev=
elopers prefer OP_CAT.
<br>> > > > > >
<br>> > > > > > Not convinced it is impossible that there=
is no way to simulate CAT with PAIRCOMMIT, nor confident how much less pow=
erful PAIRCOMMIT is than CAT.
<br>> > > > > >
<br>> > > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D
<br>> > > > > > OP_CHECKTEMPLATEVERIFY
<br>> > > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D
<br>> > > > > >
<br>> > > > > > Limited in scope and not recursive.
<br>> > > > > > ```
<br>> > > > > >
<br>> > > > > > I have tried my best to remain unbiased i=
n writing this summary and approving edits. There are a few things that I w=
ant to share and it could be a result of the aggressive marketing:
<br>> > > > > >
<br>> > > > > > - A spammer had edited the table to remov=
e all evaluations except in favor of OP_CAT and it was rejected.
<br>> > > > > > - [Rationale][6] added by Aaron (sCrypt) =
does not mention anything about other opcodes and SIGHASH_APO. It is only f=
ocused on OP_CAT however evaluations exist in the table.
<br>> > > > > > - I [requested][7] Udev (CatSwap) to add =
details about evaluation of other opcodes and SIGHASH_APO.
<br>> > > > > > - Last [edit][8] by Roujiamo (bitdollar) =
has a rationale with incorrect signet stats and seems to be rephrased versi=
on of another rationale. Evaluation had 'weak' for OP_CTV before ad=
ding the rationale.
<br>> > > > > > - An edit with duplicate rationale (in su=
pport of OP_CAT) was rejected because sharing the link for a rationale subm=
itted by other developer adds no value in the table.
<br>> > > > > >
<br>> > > > > > Evaluations without a rationale have some=
'No' in different cells. Although none of them are backed by a rat=
ionale so cannot be considered for consensus discussion. The table is still=
updated regularly so you may see some of them with a rationale in 2025. An=
y suggestions to help achieve technical consensus are most welcome.
<br>> > > > > >
<br>> > > > > > What's next?
<br>> > > > > >
<br>> > > > > > - More rationales in the table
<br>> > > > > > - Discuss objections on mailing list (if =
any)
<br>> > > > > > - Workshops
<br>> > > > > > - Add a table for economic nodes and thei=
r opinion
<br>> > > > > > - Build activation client and discuss par=
ameters
<br>> > > > > >
<br>> > > > > > Finally, I would thank all the developers=
who added their evaluations in the table and everyone who shared updates o=
n twitter. It was a coordinated effort to reach some technical consensus. Y=
ou can read all the rationales in detail to understand different perspectiv=
es and reasons to support a combination of opcodes over others.
<br>> > > > > >
<br>> > > > > > [1]: <a href=3D"https://groups.google.com=
/g/bitcoindev/c/fdxkE1Al4TI/m/CeEuls2IAQAJ" target=3D"_blank" rel=3D"nofoll=
ow" data-saferedirecturl=3D"https://www.google.com/url?hl=3Den&q=3Dhttp=
s://groups.google.com/g/bitcoindev/c/fdxkE1Al4TI/m/CeEuls2IAQAJ&source=
=3Dgmail&ust=3D1736950171965000&usg=3DAOvVaw3bOR11RN0ICQwdtzFtM2oO"=
>https://groups.google.com/g/bitcoindev/c/fdxkE1Al4TI/m/CeEuls2IAQAJ</a>
<br>> > > > > > [2]: <a href=3D"https://bitcoinops.org/en=
/podcast/2024/12/17/" target=3D"_blank" rel=3D"nofollow" data-saferedirectu=
rl=3D"https://www.google.com/url?hl=3Den&q=3Dhttps://bitcoinops.org/en/=
podcast/2024/12/17/&source=3Dgmail&ust=3D1736950171965000&usg=
=3DAOvVaw1YNRFxey7uB-En-XmoU2Wv">https://bitcoinops.org/en/podcast/2024/12/=
17/</a>
<br>> > > > > > [3]: <a href=3D"https://en.bitcoin.it/wik=
i/Covenants_Uses" target=3D"_blank" rel=3D"nofollow" data-saferedirecturl=
=3D"https://www.google.com/url?hl=3Den&q=3Dhttps://en.bitcoin.it/wiki/C=
ovenants_Uses&source=3Dgmail&ust=3D1736950171965000&usg=3DAOvVa=
w1Zz9_cF_YEmn8e3fPJRRWL">https://en.bitcoin.it/wiki/Covenants_Uses</a>
<br>> > > > > > [4]: <a href=3D"https://github.com/bitcoi=
n/bips/blob/master/bip-0348.md" target=3D"_blank" rel=3D"nofollow" data-saf=
eredirecturl=3D"https://www.google.com/url?hl=3Den&q=3Dhttps://github.c=
om/bitcoin/bips/blob/master/bip-0348.md&source=3Dgmail&ust=3D173695=
0171965000&usg=3DAOvVaw23Tdty6toDC934hdZvyUIP">https://github.com/bitco=
in/bips/blob/master/bip-0348.md</a>
<br>> > > > > > [5]: <a href=3D"https://gist.github.com/A=
deman/4a14614fa850511d63a5b2a9b5104cb7" target=3D"_blank" rel=3D"nofollow" =
data-saferedirecturl=3D"https://www.google.com/url?hl=3Den&q=3Dhttps://=
gist.github.com/Ademan/4a14614fa850511d63a5b2a9b5104cb7&source=3Dgmail&=
amp;ust=3D1736950171965000&usg=3DAOvVaw1xIA-WtF3DlkCJ1BvIDp-J">https://=
gist.github.com/Ademan/4a14614fa850511d63a5b2a9b5104cb7</a>
<br>> > > > > > [6]: <a href=3D"https://gist.github.com/g=
itzhou/dc92c41db1987db16fe665c26bc56dd9" target=3D"_blank" rel=3D"nofollow"=
data-saferedirecturl=3D"https://www.google.com/url?hl=3Den&q=3Dhttps:/=
/gist.github.com/gitzhou/dc92c41db1987db16fe665c26bc56dd9&source=3Dgmai=
l&ust=3D1736950171965000&usg=3DAOvVaw065hUCINbNQwfEpt8mnCK5">https:=
//gist.github.com/gitzhou/dc92c41db1987db16fe665c26bc56dd9</a>
<br>> > > > > > [7]: <a href=3D"https://gist.github.com/u=
devswap/b768d20d62549922b9e72428ef9eb608?permalink_comment_id=3D5359072#gis=
tcomment-5359072" target=3D"_blank" rel=3D"nofollow" data-saferedirecturl=
=3D"https://www.google.com/url?hl=3Den&q=3Dhttps://gist.github.com/udev=
swap/b768d20d62549922b9e72428ef9eb608?permalink_comment_id%3D5359072%23gist=
comment-5359072&source=3Dgmail&ust=3D1736950171965000&usg=3DAOv=
Vaw3-8Y6DrPS4XJjSk_ipDeX-">https://gist.github.com/udevswap/b768d20d6254992=
2b9e72428ef9eb608?permalink_comment_id=3D5359072#gistcomment-5359072</a>
<br>> > > > > > [8]: <a href=3D"https://en.bitcoin.it/w/i=
ndex.php?title=3DCovenants_support&diff=3Dprev&oldid=3D70520" targe=
t=3D"_blank" rel=3D"nofollow" data-saferedirecturl=3D"https://www.google.co=
m/url?hl=3Den&q=3Dhttps://en.bitcoin.it/w/index.php?title%3DCovenants_s=
upport%26diff%3Dprev%26oldid%3D70520&source=3Dgmail&ust=3D173695017=
1965000&usg=3DAOvVaw1ZmVTfPkg4HpgippH-tAJK">https://en.bitcoin.it/w/ind=
ex.php?title=3DCovenants_support&diff=3Dprev&oldid=3D70520</a>
<br>> > > > > >
<br>> > > > > > /dev/fd0
<br>> > > > > > floppy disk guy
<br>> > > > > >
<br>> > > > > > --
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