Bitcoin Optech

Bitcoin Optech newsletter #305 is here:
- describes a proposed light client protocol for silent payments
- summarizes two new proposed descriptors for taproot
- links to a discussion about whether opcodes with overlapping features should be added in a soft fork
- summarizes popular Q&A from Stack Exchange
- Optech Newsletter #305 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2024/05/31/
Setor Blagogee posted to Delving Bitcoin to describe a draft specification for a protocol to help lightweight clients receive silent payments (SPs)...
https://bitcoinops.org/en/newsletters/2024/05/31/#light-client-protocol-for-silent-payments
Oghenovo Usiwoma posted to Delving Bitcoin about two new proposed descriptors for constructing taproot spend conditions...
https://bitcoinops.org/en/newsletters/2024/05/31/#raw-taproot-descriptors
Pierre Rochard asks if proposed soft forks that can provide much of the same features at a similar cost should be considered mutually exclusive, or whether it would make sense to activate multiple proposals and let developers use whichever alternative they prefer...
https://bitcoinops.org/en/newsletters/2024/05/31/#should-overlapping-soft-fork-proposals-be-considered-mutually-exclusive
Selected Q&A from Bitcoin Stack Exchange:
- What’s the smallest possible coinbase tx / block size?
- Understanding Script’s number encoding, CScriptNum
- Is there a way to make an address public but hide how many BTC it contains?
- Testing increased feerates in regtest
- Why is my P2P_V2 peer connected over a v1 connection?
- Does a P2PKH tx send to the hash of the uncompressed or compressed key?
- What are different ways to broadcast a block to the Bitcoin network?
https://bitcoinops.org/en/newsletters/2024/05/31/#selected-qa-from-bitcoin-stack-exchange
Bitcoin Optech will host an audio recap discussion of this newsletter with special guests Oghenovo Usiwoma and Pierre Rochard on Twitter Spaces Tuesday at 14:30 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1eaKbgnYgOBGX

2024-05-24 17:30:05

Bitcoin Optech newsletter #304 is here:
- summarizes analysis of upgrading LN channels w/o closing/reopening them
- discusses challenges ensuring pool miners are paid appropriately
- links to discussion about using PSBTs for silent payments
- announces proposed miniscript BIP
- summarizes a proposal for frequent rebalancing of an LN channel to simulate a futures contract
- summarizes changes to services/client software
- adds a pooled mining topic
- Newsletter #304 Recap
https://bitcoinops.org/en/newsletters/2024/05/24/
Carla Kirk-Cohen posted to Delving Bitcoin a summary and analysis of existing proposals for upgrading existing LN channels to support new features. She examines a variety of different cases and compares three previously proposed ideas for upgrading channels...
https://bitcoinops.org/en/newsletters/2024/05/24/#upgrading-existing-ln-channels
Ethan Tuttle posted to Delving Bitcoin to suggest that mining pools could reward miners with ecash tokens proportionate to the number of shares they mined...
https://bitcoinops.org/en/newsletters/2024/05/24/#challenges-in-rewarding-pool-miners
Josie Baker started a discussion on Delving Bitcoin about PSBT extensions for silent payments (SPs), citing a draft specification by Andrew Toth...
https://bitcoinops.org/en/newsletters/2024/05/24/#discussion-about-psbts-for-silent-payments
Ava Chow posted to the Bitcoin-Dev mailing list a draft BIP for miniscript...
https://bitcoinops.org/en/newsletters/2024/05/24/#proposed-miniscript-bip
Tony Klausing posted to Delving Bitcoin a proposal, with working code, for stable channels...
https://bitcoinops.org/en/newsletters/2024/05/24/#channel-value-pegging
Changes to services and client software:
- Silent payment resources
- Cake Wallet adds silent payments
- Coordinator-less coinjoin PoC
- OCEAN adds BOLT12 support
- Coinbase adds Lightning support
- Bitcoin escrow tooling announced
- Block’s call for mining community feedback
- Sentrum wallet tracker released
- Stack Wallet adds FROST support
- Transaction broadcast tool announced
https://bitcoinops.org/en/newsletters/2024/05/24/#changes-to-services-and-client-software
Pooled mining occurs when two or more independent miners collaborate on finding proof of work for new blocks, with them fairly dividing the rewards of any blocks they find...
https://bitcoinops.org/en/topics/pooled-mining/
Bitcoin Optech will host an audio recap discussion of this newsletter with special guests Andrew Toth, ⁨Antoine Poinsot⁩, and Tony Klausing on Twitter Spaces Monday at 14:30 UTC. Join us to discuss or ask questions!
https://x.com/i/spaces/1nAKEaAkVzVKL

2024-05-17 12:42:19

Bitcoin Optech newsletter #303 is here:
- summarizes a new scheme for anonymous usage tokens that could be used for LN channel announcements and other sybil-resistant coordination protocols
- links to discussion about a new BIP39 seed phrase splitting scheme
- announces an alternative to BitVM for verifying successful execution of arbitrary programs in interactive contract protocols
- relays suggestions for updating the BIPs process
- Optech Newsletter #303 Recap
https://bitcoinops.org/en/newsletters/2024/05/17/
Adam Gibson posted to Delving Bitcoin about a scheme he has developed to allow anyone who can keypath-spend a UTXO to prove they could spend it without revealing which UTXO it is...
https://bitcoinops.org/en/newsletters/2024/05/17/#anonymous-usage-tokens
Rama Gan posted to the Bitcoin-Dev mailing list a link to a set of tools they have developed for generating and splitting a BIP39 seed phrase without using any electronic computing equipment...
https://bitcoinops.org/en/newsletters/2024/05/17/#bip39-seed-phrase-splitting
Sergio Demian Lerner and several co-authors posted to the Bitcoin-Dev mailing list about a new virtual CPU architecture based in part on the ideas behind BitVM. The goal of their project, BitVMX, is to be able to efficiently prove the proper execution of any program that can be compiled to run on an established CPU architecture, such as RISC-V...
https://bitcoinops.org/en/newsletters/2024/05/17/#alternative-to-bitvm
Mark “Murch” Erhardt continued the discussion on the Bitcoin-Dev mailing list about updating BIP2, which is the document that currently describes the Bitcoin improvement proposals (BIP) process...
https://bitcoinops.org/en/newsletters/2024/05/17/#continued-discussion-about-updating-bip2
Bitcoin Optech will host an audio recap discussion of this newsletter on Twitter Spaces Tuesday (note the day change) at 14:30 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1MnxnMQOdOYJO

2024-05-15 13:08:45

Bitcoin Optech newsletter #302 is here:
- announces the beta release of a full node supporting utreexo
- summarizes two proposed extensions to BIP119 OP_CHECKTEMPLATEVERIFY
- Optech Newsletter #302 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2024/05/15/
Calvin Kim posted to the Bitcoin-Dev mailing list to announce the beta release of utreexod, a full node with support for utreexo. Utreexo allows a node to store a small commitment to the state of the UTXO set rather than the entire set itself...
https://bitcoinops.org/en/newsletters/2024/05/15/#release-of-utreexod-beta
Jeremy Rubin posted to the Bitcoin-Dev mailing list a proposed BIP to extend the proposed OP_CHECKTEMPLATEVERIFY (OP_CTV) with two additional features...
https://bitcoinops.org/en/newsletters/2024/05/15/#bip119-extensions-for-smaller-hashes-and-arbitrary-data-commitments
Bitcoin Optech will host an audio recap discussion of this newsletter on Twitter Spaces Thursday at 14:30 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1PlJQDVMBWaGE

2024-05-08 13:22:35

Bitcoin Optech newsletter #301 is here:
- describes an idea for securing transactions with lamport signatures without requiring any consensus changes
- recaps the "Index TxOrphanage by wtxid, allow entries with same txid" PR Review Meeting
- Optech Newsletter #301 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2024/05/08/
Ethan Heilman posted to the Bitcoin-Dev mailing list a method for requiring that a transaction be signed by a lamport signature in order to be valid...
https://bitcoinops.org/en/newsletters/2024/05/08/#consensus-enforced-lamport-signatures-on-top-of-ecdsa-signatures
Index TxOrphanage by wtxid, allow entries with same txid is a PR by Gloria Zhao that allows multiple transactions with the same txid to exist in TxOrphanage at the same time by indexing them on wtxid instead of txid...
https://bitcoinops.org/en/newsletters/2024/05/08/#bitcoin-core-pr-review-club
Bitcoin Optech will host an audio recap discussion of this newsletter with special guests Ethan Heilman and Gloria Zhao on Twitter Spaces Thursday at 14:30 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1RDGllvgewVGL

2024-05-01 12:22:43

Bitcoin Optech newsletter #300 is here:
- summarizes a CTV-like proposal that uses commitments embedded in public keys
- examines the analysis of a contract protocol with Alloy
- announces the arrests of Bitcoin developers
- links to summaries of a CoreDev.tech developer meetup
- Optech Newsletter #300 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2024/05/01/
Tadge Dryja posted to Delving Bitcoin a proposal for a slightly more efficient version of the core idea of OP_CHECKTEMPLATEVERIFY (CTV)...
https://bitcoinops.org/en/newsletters/2024/05/01/#ctv-like-exploding-keys-proposal
Dmitry Petukhov posted to Delving Bitcoin a specification he had created using the Alloy specification language for the simple OP_CAT-based vault. Petukhov used Alloy to find several useful modifications and to highlight important constraints that any potential implementors should observe...
https://bitcoinops.org/en/newsletters/2024/05/01/#analyzing-a-contract-protocol-with-alloy
As widely reported elsewhere, two developers of the Samourai privacy-enhanced Bitcoin wallet were arrested last week in relation to their software, based on charges by U.S. law enforcement...
https://bitcoinops.org/en/newsletters/2024/05/01/#arrests-of-bitcoin-developers
Many Bitcoin Core contributors met in person for a periodic CoreDev.tech event last month in Berlin. Transcripts for some of the sessions from the event have been provided by attendees...
https://bitcoinops.org/en/newsletters/2024/05/01/#coredev-tech-berlin-event
Bitcoin Optech will host an audio recap discussion of this newsletter with special guest Tadge Dryja on Twitter Spaces Thursday at 14:30 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1LyxBnyAnnjxN

2024-04-24 13:25:47

Bitcoin Optech newsletter #299 is here:
- newsletter describes a proposal to relay weak blocks to improve compact block performance in a network with multiple divergent mempool policies
- announces the addition of five BIP editors
- summarizes popular Q&A from Stack Exchange
- Optech Newsletter #299 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2024/04/24/
Greg Sanders posted to Delving Bitcoin about using weak blocks to improve compact block relay, particularly in the presence of divergent policies for transaction relay and mining. A weak block is a block with insufficient proof-of-work (PoW) to become the next block on the blockchain but which otherwise has a valid structure and set of valid transactions...
https://bitcoinops.org/en/newsletters/2024/04/24/#weak-blocks-proof-of-concept-implementation
After public discussion, the following contributors have been made BIP editors: Bryan “Kanzure” Bishop, Jon Atack, Mark “Murch” Erhardt, Olaoluwa “Roasbeef” Osuntokun, and Ruben Somsen.
https://bitcoinops.org/en/newsletters/2024/04/24/#bip-editors-update
Selected Q&A from Bitcoin Stack Exchange:
- Where exactly is the “off-by-one” difficulty bug?
- How is P2TR different than P2PKH using opcodes from a developer perspective?
- Are replacement transactions larger in size than their predecessors and than non-RBF transactions?
- Are Bitcoin signatures still vulnerable to nonce reuse?
- How do miners manually add transactions to a block template?
https://bitcoinops.org/en/newsletters/2024/04/24/#selected-qa-from-bitcoin-stack-exchange
Bitcoin Optech will host an audio recap discussion of this newsletter with special guest Gregory Sanders on Twitter Spaces Thursday at 14:30 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1nAKEaQWybkKL

2024-04-17 11:35:29

Bitcoin Optech newsletter #298 is here:
- summarizes an analysis of how a node with cluster mempool behaved when tested with all transactions seen on the network in 2023
- Bitcoin Core 27.0 release
- summarizes changes to services/client software
- Optech Newsletter #298 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2024/04/17/
Suhas Daftuar posted to Delving Bitcoin that he recorded every transaction his node received in 2023 and has now run them through a development version of Bitcoin Core with cluster mempool enabled to quantify differences between the existing version and the development version...
https://bitcoinops.org/en/newsletters/2024/04/17/#what-would-have-happened-if-cluster-mempool-had-been-deployed-a-year-ago
Changes to services and client software:
- Phoenix for server announced
- Mercury Layer adds Lightning swaps
- Stratum V2 Reference Implementation v1.0.0 released
- Teleport Transactions update
- Bitcoin Keeper v1.2.1 released
- BIP-329 label management software
- Key agent Sigbash launches
https://bitcoinops.org/en/newsletters/2024/04/17/#changes-to-services-and-client-software
Bitcoin Core 27.0 is the release of the next major version of the network’s predominant full node implementation...
https://bitcoinops.org/en/newsletters/2024/04/17/#bitcoin-core-27-0
Bitcoin Optech will host an audio recap discussion of this newsletter on Twitter Spaces Thursday at 14:30 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1OyJAWNAezaKb

2024-04-10 09:53:02

Bitcoin Optech newsletter #297 is here:
- announces a new domain-specific language for experimenting with contract protocols
- summarizes a discussion about modifying BIP editor responsibilities
- describes proposals to reset and modify testnet
- recaps the "Implement 64 bit arithmetic op codes in the Script interpreter" PR Review Meeting
- Optech Newsletter #297 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2024/04/10/
Kulpreet Singh posted to Delving Bitcoin about a domain-specific language (DSL) he’s working on for Bitcoin. The language makes it easy to specify the operations that should be performed as part of a contract protocol...
https://bitcoinops.org/en/newsletters/2024/04/10/#dsl-for-experimenting-with-contracts
Tim Ruffing posted to the Bitcoin-Dev mailing list about updating BIP2, which specifies the current process for adding new BIPs and updating existing BIPs...
https://bitcoinops.org/en/newsletters/2024/04/10/#updating-bip2
Jameson Lopp posted to the Bitcoin-Dev mailing list about problems with the current public Bitcoin testnet (testnet3) and suggested restarting it, potentially with a different set of special-case consensus rules...
https://bitcoinops.org/en/newsletters/2024/04/10/#discussion-about-resetting-and-modifying-testnet
'Implement 64 bit arithmetic op codes in the Script interpreter' is a PR by Chris Stewart (GitHub Christewart) that introduces new opcodes allowing users to perform arithmetic operations on larger (64-bit) operands in Bitcoin Script than is currently allowed (32-bit)...
https://bitcoinops.org/en/newsletters/2024/04/10/#bitcoin-core-pr-review-club
Bitcoin Optech will host an audio recap discussion of this newsletter with special guests Kulpreet Singh, Jameson Lopp, and Joost Jager on Twitter Spaces Thursday at 16:00 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1YpKkwWomVMKj

2024-04-03 14:42:17

Bitcoin Optech newsletter #296 is here:
- summarizes discussion about a new push for a consensus cleanup soft fork
- announces a plan to choose additional BIP editors
- adds an accidental confiscation topic
- adds a duplicate transactions topic
- adds a gap limit topic
- adds a time warp topic
- Optech Newsletter #296 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2024/04/03/
Antoine Poinsot posted to Delving Bitcoin about revisiting Matt Corallo’s consensus cleanup proposal from 2019...
https://bitcoinops.org/en/newsletters/2024/04/03/#revisiting-consensus-cleanup
Mark “Murch” Erhardt continued the thread about adding new BIP editors by proposing everyone express “their arguments for and against any candidates in this thread until Friday end-of-day (April 5th)...
https://bitcoinops.org/en/newsletters/2024/04/03/#choosing-new-bip-editors
Accidental confiscation can occur if a poorly designed soft fork permanently prevents a user from being able to get a transaction confirmed...
https://bitcoinops.org/en/topics/accidental-confiscation/
Duplicate transactions are more than one transaction that are identical and have identical txids. Bitcoin’s consensus rules use txids to uniquely identify transactions, so duplicate transactions can cause unwanted behavior...
https://bitcoinops.org/en/topics/duplicate-transactions/
Gap limits are the limits wallets set for how many addresses they’ll derive from an HD wallet without seeing any transactions related to those addresses...
https://bitcoinops.org/en/topics/gap-limits/
Time warp is an exploit of Bitcoin’s difficulty adjustment algorithm that allows miners controlling a large amount of hashrate to prevent difficulty from increasing even as the rate of block production increases...
https://bitcoinops.org/en/topics/time-warp/
Bitcoin Optech will host an audio recap discussion of this newsletter with special guest Antoine Poinsot on Twitter Spaces Thursday at 14:30 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1vOxwjOPWrdJB?s=20

2024-03-27 11:38:14

Bitcoin Optech newsletter #295 is here:
- announces the disclosure of a bandwidth-wasting attack affecting Bitcoin Core and related nodes
- describes several improvements to the idea for transaction fee sponsorship
- summarizes a discussion about using live mempool data to improve Bitcoin Core’s feerate estimation
- summarizes popular Q&A from Stack Exchange
- Bitcoin Core 27.0rc1 testing guide
- adds a free relay topic
- Optech Newsletter #295 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2024/03/27/
A bandwidth-wasting attack was described to the Bitcoin-Dev mailing list. In short, Mallory broadcasts one version of a transaction to Alice and a different version of the transaction to Bob...
https://bitcoinops.org/en/newsletters/2024/03/27/#disclosure-of-free-relay-attack
Martin Habovštiak posted to the Bitcoin-Dev mailing list an idea for allowing one transaction to boost the priority of an unrelated transaction...
https://bitcoinops.org/en/newsletters/2024/03/27/#transaction-fee-sponsorship-improvements
Abubakar Sadiq Ismail posted to Delving Bitcoin about improving Bitcoin Core’s feerate estimation using data from a node’s local mempool...
https://bitcoinops.org/en/newsletters/2024/03/27/#mempool-based-feerate-estimation
Selected Q&A from Bitcoin Stack Exchange:
- What are the risks of running a pre-SegWit node (0.12.1)?
- When is OP_RETURN cheaper than OP_FALSE OP_IF?
- Why does BIP-340 use secp256k1?
- What criteria does Bitcoin Core use to create block templates?
- How does the initialblockdownload field in the getblockchaininfo RPC work?
https://bitcoinops.org/en/newsletters/2024/03/27/#selected-qa-from-bitcoin-stack-exchange
Bitcoin Core 27.0rc1 has a brief overview to suggested testing topics and a scheduled meeting of the Bitcoin Core PR Review Club dedicated to testing today (March 27th) at 15:00 UTC.
https://bitcoincore.reviews/v27-rc-testing
https://github.com/bitcoin-core/bitcoin-devwiki/wiki/27.0-Release-Candidate-Testing-Guide
Free relay was a policy on early Bitcoin full nodes to allow some unconfirmed transactions to be relayed even if they didn’t pay transaction fees. That policy allowed an attacker to waste the bandwidth of full nodes without paying any cost, so modern full nodes generally try to forbid operations which don’t allow miners to claim fees that are proportionate to the amount of relay bandwidth used...
https://bitcoinops.org/en/topics/free-relay/
Bitcoin Optech will host an audio recap discussion of this newsletter with special guests Dave Harding, Peter Todd, Abubakar Sadiq Ismail, David Gumberg, and Jeffrey Czyz on Twitter Spaces Thursday at 14:30 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1ZkKzjyQPNRKv

2024-03-20 12:20:56

Bitcoin Optech newsletter #294 is here:
- announces a project to create a BIP324 proxy for light clients
- summarizes discussion about a proposed BTC Lisp language
- summarizes changes to services/client software
- adds a Kindred replace by fee topic
- Optech #294 Recap
https://bitcoinops.org/en/newsletters/2024/03/20/
Sebastian Falbesoner posted to Delving Bitcoin to announce a TCP proxy for translating between the version 1 (v1) Bitcoin P2P protocol and the v2 protocol defined in BIP324. This is especially intended to allow light client wallets written for v1 to take advantage of v2’s traffic encryption...
https://bitcoinops.org/en/newsletters/2024/03/20/#bip324-proxy-for-light-clients
Anthony Towns posted to Delving Bitcoin about his experiments over the past couple of years creating a variant of the Lisp language for Bitcoin, called BTC Lisp. See Newsletters #293 and #191 for previous discussions...
https://bitcoinops.org/en/newsletters/2024/03/20/#overview-of-btc-lisp
Changes to services and client software:
- BitGo adds RBF support
- Phoenix Wallet v2.2.0 released
- Bitkey hardware signing device released
- Envoy v1.6.0 released
- VLS v0.11.0 released
- Portal hardware signing device announced
- Braiins mining pool adds Lightning support
- Ledger Bitcoin App 2.2.0 released
https://bitcoinops.org/en/newsletters/2024/03/20/#changes-to-services-and-client-software
Kindred replace by fee is the ability for a transaction to replace a related transaction in the mempool even if there’s no conflict between the two transactions...
https://bitcoinops.org/en/topics/kindred-replace-by-fee/
Bitcoin Optech will host an audio recap discussion of this newsletter with special guests Sebastian Falbesoner, Anthony Towns, and Russell O’Connor on Twitter Spaces Thursday at 14:30 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1ZkKzjEzkjyKv

2024-03-13 11:59:03

Bitcoin Optech newsletter #293 is here:
- summarizes a post about trustless onchain betting for potential soft forks
- links to a detailed overview of Chia Lisp for Bitcoiners
- recaps the "Re enable OP_CAT" PR Review Meeting
- Core Lightning v24.02.1, Bitcoin Core 26.1rc1, Bitcoin Core 27.0rc1 release candidates
https://bitcoinops.org/en/newsletters/2024/03/13/
ZmnSCPxj posted to Delving Bitcoin a protocol for giving control over a UTXO to a party that correctly predicts whether or not a particular soft fork will activate...
https://bitcoinops.org/en/newsletters/2024/03/13/#trustless-onchain-betting-on-potential-soft-forks
Anthony Towns posted to Delving Bitcoin a detailed overview of the Lisp variant used by the Chia cryptocurrency...
https://bitcoinops.org/en/newsletters/2024/03/13/#overview-of-chia-lisp-for-bitcoiners
'Re enable OP_CAT' is a PR by Armin Sabouri (GitHub 0xBEEFCAF3) that reintroduces the OP_CAT opcode but only on signet Bitcoin Inquisition and only for tapscript (taproot script)...
https://bitcoinops.org/en/newsletters/2024/03/13/#bitcoin-core-pr-review-club
Bitcoin Core 27.0rc1 is a release candidate for the next major version of the network’s predominant full node implementation.
https://bitcoinops.org/en/newsletters/2024/03/13/#bitcoin-core-27-0rc1
Bitcoin Optech will host an audio recap discussion of this newsletter on Twitter Spaces Thursday at 14:00 UTC (new time!). Join us to discuss or ask questions!
https://twitter.com/i/spaces/1ynKOyNnAprJR

2024-03-06 10:53:24

Bitcoin Optech newsletter #292 is here:
- summarizes a discussion about updating the specification for BIP21 bitcoin: URIs
- describes a proposal to manage multiple concurrent MuSig2 signing sessions with a minimum of state
- links to a thread about adding editors for the BIPs repository
- discusses a set of tools that allow quickly porting the Bitcoin Core GitHub project to a self-hosted GitLab project
- Optech Newsletter #292 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2024/03/06/
Josie Baker posted to Delving Bitcoin to discuss how BIP21 URIs are specified to be used, how they’re used today, and how they can be used in the future...
https://bitcoinops.org/en/newsletters/2024/03/06/#updating-bip21-bitcoin-uris
Salvatore Ingala posted to Delving Bitcoin about minimizing the amount of state needed to perform multiple MuSig2 signing sessions in parallel...
https://bitcoinops.org/en/newsletters/2024/03/06/#psbts-for-multiple-concurrent-musig2-signing-sessions
Ava Chow posted to the Bitcoin-Dev mailing list to suggest the addition of BIP editors to help the current editor...
https://bitcoinops.org/en/newsletters/2024/03/06/#discussion-about-adding-more-bip-editors
Fabian Jahr posted to Delving Bitcoin about maintaining a backup of the Bitcoin Core project’s GitHub account on a self-hosted GitLab instance. In case the project ever needed to leave GitHub suddenly, this would make all existing issues and pull requests accessible on GitLab within a short amount of time, allowing work to continue with only a brief interruption...
https://bitcoinops.org/en/newsletters/2024/03/06/#gitlab-backup-for-bitcoin-core-github-project
Bitcoin Optech will host an audio recap discussion of this newsletter with special guests Josie Baker, Salvatore Ingala, and Fabian Jahr on Twitter Spaces Thursday at 15:00 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1mnxepjZboAJX

2024-02-28 12:50:18

Bitcoin Optech newsletter #291 is here:
- describes a proposed contract for trustless miner feerate futures,
- links to a coin selection algorithm for LN nodes providing dual funding liquidity
- details a prototype for a vault using OP_CAT
- discusses sending and receiving ecash using LN and ZKCPs
- summarizes popular Q&A from Stack Exchange
- adds an Ecash topic
- Optech Newsletter #291 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2024/02/28/
ZmnSCPxj posted to Delving Bitcoin a set of scripts that will allow two parties to conditionally pay each other based on the marginal feerate to include a transaction in a future block...
https://bitcoinops.org/en/newsletters/2024/02/28/#trustless-contract-for-miner-feerate-futures
Richard Myers posted to Delving Bitcoin about creating a coin selection algorithm that is optimized for LN nodes offering liquidity via liquidity advertisements...
https://bitcoinops.org/en/newsletters/2024/02/28/#coin-selection-for-liquidity-providers
Developer Rijndael posted to Delving Bitcoin about a Rust-language proof-of-concept implementation he’s written for a vault that only depends on the current consensus rules plus the proposed OP_CAT opcode...
https://bitcoinops.org/en/newsletters/2024/02/28/#simple-vault-prototype-using-op-cat
Anthony Towns posted to Delving Bitcoin about linking “ecash mints to the lightning network without losing ecash’s anonymity or adding any additional trust”...
https://bitcoinops.org/en/newsletters/2024/02/28/#sending-and-receiving-ecash-using-ln-and-zkcps
Selected Q&A from Bitcoin Stack Exchange:
- Why can’t nodes have the relay option to disallow certain transaction types?
- What is the circular dependency in signing a chain of unconfirmed transactions?
- How does Ocean’s TIDES payout scheme work?
- What data does the Bitcoin Core wallet search for during a blockchain rescan?
- How does transaction rebroadcasting for watch-only wallets work?
https://bitcoinops.org/en/newsletters/2024/02/28/#selected-qa-from-bitcoin-stack-exchange
Ecash is a type of centralized digital currency that uses blind signatures to prevent the centralized controlling party (the mint) from knowing the balance of any particular user or from learning which users were involved in any transactions...
https://bitcoinops.org/en/topics/ecash/
Bitcoin Optech will host an audio recap discussion of this newsletter with special guests Richard Myers and Rijndael on Twitter Spaces Thursday at 15:00 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1RDGllLMreoGL

2024-02-21 12:56:41

Bitcoin Optech newsletter #290 is here:
- describes a proposal for providing DNS-based human-readable Bitcoin payment instructions
- summarizes a post with thoughts about mempool incentive compatibility
- links to a thread discussing the design of Cashu and other ecash systems
- looks at continuing discussion about 64-bit arithmetic
- gives an overview of an improved reproducible ASMap creation process
- summarizes changes to services/client software
- Optech #290 Recap
https://bitcoinops.org/en/newsletters/2024/02/21/
Following previous discussions, Matt Corallo posted to Delving Bitcoin a draft BIP that will allow a string like [email protected] to resolve to DNS address such as example.user._bitcoin-payment.example.com...
https://bitcoinops.org/en/newsletters/2024/02/21/#dns-based-human-readable-bitcoin-payment-instructions
Suhas Daftuar posted to Delving Bitcoin several insights into the criteria full nodes can use to select which transactions to accept into their mempools, relay to other nodes, and mine for maximal revenue...
https://bitcoinops.org/en/newsletters/2024/02/21/#thinking-about-mempool-incentive-compatibility
Several weeks ago, developer Thunderbiscuit posted to Delving Bitcoin a description of the blind signature scheme behind the Chaumian ecash system used in Cashu, which denominates balances in satoshis and allows sending and receiving money using Bitcoin and LN...
https://bitcoinops.org/en/newsletters/2024/02/21/#cashu-and-other-ecash-system-design-discussion
Several developers have continued discussing a potential future soft fork that could add 64-bit arithmetic operations to Bitcoin.
This week, Chris Stewart created a new discussion thread for a draft BIP for an opcode originally proposed as part of OP_TAPLEAF_UPDATE_VERIFY, OP_INOUT_AMOUNT...
https://bitcoinops.org/en/newsletters/2024/02/21/#continued-discussion-about-64-bit-arithmetic-and-op-inout-amount-opcode
Fabian Jahr posted to Delving Bitcoin about advancements in creating a map of autonomous systems (ASMap) that each control the routing for large parts of the internet...
https://bitcoinops.org/en/newsletters/2024/02/21/#improved-reproducible-asmap-creation-process
Changes to services and client software:
- Multiparty coordination protocol NWC announced
- Mutiny Wallet v0.5.7 released
- GroupHug transaction batching service
- Boltz announces taproot swaps
https://bitcoinops.org/en/newsletters/2024/02/21/#changes-to-services-and-client-software
Bitcoin Optech will host an audio recap discussion of this newsletter with special guests callebtc, Chris Stewart, and Fabian Jahr on Twitter Spaces Thursday at 15:00 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1kvJpvpWjwwKE

2024-02-14 12:56:12

Bitcoin Optech newsletter #289 is here:
- summarizes ideas for relay enhancements after cluster mempool is deployed
- describes research into the topologies and sizes of LN-style anchor outputs in 2023
- announces a new host for the Bitcoin-Dev mailing list
- encourages readers to celebrate I Love Free Software Day by thanking free software contributors
- recaps the "Add maxfeerate and maxburnamount args to submitpackage" PR Review Meeting
- Newsletter #289 Recap
https://bitcoinops.org/en/newsletters/2024/02/14/
Gregory Sanders posted to Delving Bitcoin several ideas for allowing individual transactions to opt-in to certain mempool policies after cluster mempool support has been fully implemented, tested, and deployed...
https://bitcoinops.org/en/newsletters/2024/02/14/#ideas-for-relay-enhancements-after-cluster-mempool-is-deployed
Suhas Daftuar posted to Delving Bitcoin about his research into the idea of automatically applying v3 transaction relay policy to anchors-style LN commitment and fee-bumping transactions...
https://bitcoinops.org/en/newsletters/2024/02/14/#what-would-have-happened-if-v3-semantics-had-been-applied-to-anchor-outputs-a-year-ago
The Bitcoin protocol development discussion mailing list is now hosted on a new server with a new email address. Everyone who wishes to continue receiving posts needs to resubscribe...
https://bitcoinops.org/en/newsletters/2024/02/14/#bitcoin-dev-mailing-list-move
Every year on February 14th, organizations such as FSF and FSFE encourage users of free and open source software (FOSS) to “reach out and say ‘Thank you!’ to all the people maintaining and contributing to Free Software”...
https://bitcoinops.org/en/newsletters/2024/02/14/#i-love-free-software-day
'Add maxfeerate and maxburnamount args to submitpackage' is a PR by Greg Sanders (GitHub instagibbs) that adds functionality to the submitpackage RPC that is already present in the single-transaction RPCs sendrawtransaction and testmempoolaccept...
https://bitcoinops.org/en/newsletters/2024/02/14/#bitcoin-core-pr-review-club
Bitcoin Optech will host an audio recap discussion of this newsletter with special guest Gregory Sanders on Twitter Spaces Thursday at 15:00 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1DXxyjlmXrbKM

2024-02-07 15:21:38

Bitcoin Optech newsletter #288 is here:
- announces the disclosure of a block stalling bug in Bitcoin Core affecting LN
- relays a concern about how to securely open new zero-conf channels with version 3 relay
- describes a contract protocol rule when allowing an external party to contribute an input to a tx
- summarizes discussions about a proposal for new tx replacement rules to avoid pinning
- provides a brief update on the mailing list
- #288 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2024/02/07/
Eugene Siegel announced to Delving Bitcoin a bug in Bitcoin Core he had responsibly disclosed almost three years ago. Bitcoin Core 22 and higher contain fixes for the bug, but many people are still running affected versions...
https://bitcoinops.org/en/newsletters/2024/02/07/#public-disclosure-of-a-block-stalling-bug-in-bitcoin-core-affecting-ln
Matt Corallo posted to Delving Bitcoin to discuss how to securely allow zero-conf channel opening when the proposed v3 transaction relay policy is being used...
https://bitcoinops.org/en/newsletters/2024/02/07/#securely-opening-zero-conf-channels-with-v3-transactions
Bastien Teinturier posted to Delving Bitcoin to describe an easy-to-overlook requirement for protocols where a third party contributes an input to a transaction whose txid must not change after a different user contributes a signature to the transaction...
https://bitcoinops.org/en/newsletters/2024/02/07/#requirement-to-verify-inputs-use-segwit-in-protocols-vulnerable-to-txid-malleability
Peter Todd posted to the Bitcoin-Dev mailing list a proposal for a set of transaction replacement policies that can be used even when existing replace-by-fee (RBF) policies won’t allow a transaction to be replaced...
https://bitcoinops.org/en/newsletters/2024/02/07/#proposal-for-replace-by-feerate-to-escape-pinning
As of this writing, the Bitcoin-Dev mailing list is no longer accepting new emails as part of the process of migrating it to a different list server. Optech will provide an update when the migration is complete.
https://bitcoinops.org/en/newsletters/2024/02/07/#bitcoin-dev-mailing-list-migration-update
Bitcoin Optech will host an audio recap discussion of this newsletter with special guest Bastien Teinturier on Twitter Spaces Thursday at 15:00 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1OyKAWlAaewJb

2024-01-31 15:53:46

Bitcoin Optech newsletter #287 is here:
- describes a proposal to allow replacement of v3 transactions using RBF rules to ease the transition to cluster mempool
- summarizes an argument against OP_CHECKTEMPLATEVERIFY based on it commonly requiring exogenous fees
- summarizes popular Q&A from Stack Exchange
- adds a Fee sourcing topic
- adds a Simple taproot channels topic
- Optech Newsletter #287 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2024/01/31/
Gloria Zhao posted to Delving Bitcoin about allowing a transaction to replace a related transaction in the mempool even if there’s no conflict between the two transactions...
https://bitcoinops.org/en/newsletters/2024/01/31/#kindred-replace-by-fee
Peter Todd posted to the Bitcoin-Dev mailing list an adaptation of his argument against exogenous fees (see Newsletter #284) applied to the OP_CHECKTEMPLATEVERIFY proposal...
https://bitcoinops.org/en/newsletters/2024/01/31/#opposition-to-ctv-based-on-commonly-requiring-exogenous-fees
Selected Q&A from Bitcoin Stack Exchange:
- How does block synchronization work in Bitcoin Core today?
- How does headers-first prevent disk-fill attack?
- Is BIP324 v2transport redundant on Tor and I2P connections?
- What’s a rule of thumb for setting the maximum number of connections?
- Why isn’t the upper bound (+2h) on the block timestamp set as a consensus rule?
- Sigop count and its influence on transaction selection?
https://bitcoinops.org/en/newsletters/2024/01/31/#selected-qa-from-bitcoin-stack-exchange
Fee sourcing refers to the decisions made by designers of committed transactions (such as presigned transactions) about what sources of funds they’ll use for paying transaction fees...
https://bitcoinops.org/en/topics/fee-sourcing/
Simple taproot channels are LND funding and commitment transactions that use taproot (P2TR) with support for MuSig2 scriptless multisignature signing when both parties are cooperating...
https://bitcoinops.org/en/topics/simple-taproot-channels/
Bitcoin Optech will host an audio recap discussion of this newsletter with special guests Gloria Zhao and Brandon Black on Twitter Spaces Thursday at 15:00 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1lPJqblBqMexb

2024-01-24 13:35:46

Bitcoin Optech newsletter #286 is here:
- announces a fixed consensus failure in older versions of btcd
- describes proposed changes to LN for v3 transaction relay and ephemeral anchors
- announces a new repository for Bitcoin-related specifications
- summarizes changes to services/client software
- adds a Trimmed HTLC topic
- Optech Newsletter #286 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2024/01/24/
Niklas Gögge used Delving Bitcoin to announce a consensus failure in older versions of btcd that he had previously responsibly disclosed. Relative timelocks were added to Bitcoin in a soft fork by adding consensus-enforced meaning to transaction input sequence numbers...
https://bitcoinops.org/en/newsletters/2024/01/24/#disclosure-of-fixed-consensus-failure-in-btcd
Bastien Teinturier posted to Delving Bitcoin to describe the changes he thinks should be made to the LN specification to make effective use of v3 transaction relay and ephemeral anchors...
https://bitcoinops.org/en/newsletters/2024/01/24/#proposed-changes-to-ln-for-v3-relay-and-ephemeral-anchors
Anthony Towns posted to the Bitcoin-Dev mailing list to announce a new repository for protocol specifications, Bitcoin Inquisition Numbers And Names Authority (BINANA). Four specifications are available in the repository at the time of writing...
https://bitcoinops.org/en/newsletters/2024/01/24/#new-documentation-repository
Changes to services and client software:
- Envoy 1.5 released
- Liana v4.0 released
- Mercury Layer announced
- AQUA wallet announced
- Samourai Wallet announces atomic swap feature
https://bitcoinops.org/en/newsletters/2024/01/24/#changes-to-services-and-client-software
Trimmed HTLCs are forwardable LN payments that are below a channel’s economic limit for being resolved onchain. Instead, a commitment transaction that goes onchain pays the value of all trimmed HTLCs to transaction fees...
https://bitcoinops.org/en/topics/trimmed-htlc/
Bitcoin Optech will host an audio recap discussion of this newsletter with special guests Niklas Gögge, Bastien Teinturier, and Anthony Towns on Twitter Spaces Thursday at 15:00 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1YqxoDOBNRZKv

2024-01-17 13:12:38

Bitcoin Optech newsletter #285 is here:
- discloses a past vulnerability affecting Core Lightning
- announces two new soft fork proposals
- provides an overview of the cluster mempool proposal
- relays information about an updated specification and implementation of transaction compression
- summarizes a discussion about Miner Extractable Value (MEV) in non-zero ephemeral anchors
- adds an Ark topic
- Optech Newsletter #285 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2024/01/17/
Matt Morehouse used Delving Bitcoin to announce a vulnerability he had previously responsibly disclosed that affected Core Lightning versions 23.02 through 23.05.2...
https://bitcoinops.org/en/newsletters/2024/01/17/#disclosure-of-past-vulnerability-in-core-lightning
Brandon Black posted to Delving Bitcoin details about a soft fork that combines previous proposals for OP_CHECKTEMPLATEVERIFY (CTV) and OP_CHECKSIGFROMSTACK (CSFS) with a new proposal for an OP_INTERNALKEY that places the taproot internal key on the stack...
https://bitcoinops.org/en/newsletters/2024/01/17/#new-lnhance-combination-soft-fork-proposed
Chris Stewart posted a draft BIP to Delving Bitcoin for enabling 64-bit arithmetic operations on Bitcoin in a future soft fork. Bitcoin currently only allows 32-bit operations...
https://bitcoinops.org/en/newsletters/2024/01/17/#proposal-for-64-bit-arithmetic-soft-fork
Suhas Daftuar posted a summary of the cluster mempool proposal to Delving Bitcoin. Optech attempted to summarize the current state of cluster mempool discussion in Newsletter #280 but we would strongly recommend reading the overview by Daftuar, who is one of the architects of the proposal...
https://bitcoinops.org/en/newsletters/2024/01/17/#overview-of-cluster-mempool-proposal
Tom Briar posted to the Bitcoin-Dev mailing list an updated draft specification and proposed implementation of compressed Bitcoin transactions...
https://bitcoinops.org/en/newsletters/2024/01/17/#updated-specification-and-implementation-of-bitcoin-transaction-compression
Gregory Sanders posted to Delving Bitcoin to discuss concerns about ephemeral anchor outputs that contain more than 0 satoshis...
https://bitcoinops.org/en/newsletters/2024/01/17/#discussion-of-miner-extractable-value-mev-in-non-zero-ephemeral-anchors
Ark is a trustless joinpool-style protocol where a large number of users share a UTXO by accepting a counterparty as a co-signer on all transactions within a certain time period. This spreads the cost of onchain fees from using that UTXO across many users, minimizing their individual costs...
https://bitcoinops.org/en/topics/ark/
Bitcoin Optech will host an audio recap discussion of this newsletter with special guests Brandon Black, Chris Stewart, and Gregory Sanders on Twitter Spaces Thursday at 15:00 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1ypKdkjOkoYxW

2024-01-10 12:58:36

Bitcoin Optech newsletter #284 is here:
- summarizes discussion about LN anchors and elements of the v3 transaction relay proposal
- announces a research implementation of LN-Symmetry
- recaps the "Nuke adjusted time (attempt 2)" PR Review Meeting
- adds an Out-of-band fees topic
- Optech Newsletter #284 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2024/01/10/
Antoine Poinsot posted to Delving Bitcoin to foster discussion about the proposals for v3 transaction relay policy and ephemeral anchors. We’ve divided the discussion into several parts...
https://bitcoinops.org/en/newsletters/2024/01/10/#discussion-about-ln-anchors-and-v3-transaction-relay-proposal
Gregory Sanders posted to Delving Bitcoin about a proof-of-concept implementation he made of the LN-Symmetry protocol (originally called eltoo) using a software fork of Core Lightning...
https://bitcoinops.org/en/newsletters/2024/01/10/#ln-symmetry-research-implementation
Nuke adjusted time (attempt 2) is a PR by Niklas Gögge that modifies a block validity check related to the block’s timestamp...
https://bitcoinops.org/en/newsletters/2024/01/10/#bitcoin-core-pr-review-club
Out-of-band fees are payments made directly to a specific miner (or group of miners) in exchange for confirming one or more transactions. They can be contrasted with standard in-band fees that are paid using the fee implied by the difference in a transaction’s input and output value...
https://bitcoinops.org/en/topics/out-of-band-fees/
Bitcoin Optech will host an audio recap discussion of this newsletter on Twitter Spaces Thursday at 15:00 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1mnxepPqnmQJX

2024-01-03 12:14:09

Bitcoin Optech newsletter #283 is here:
- shares the disclosure of past vulnerabilities in LND
- summarizes a proposal for fee-dependent timelocks
- describes an idea for improving fee estimation using transaction clusters
- discusses how to specify unspendable keys in descriptors
- examines the cost of pinning in the v3 transaction relay proposal
- mentions a proposed BIP to allow descriptors to be included in PSBTs
- announces a tool that can be used with the MATT proposal to prove a program executed correctly
- looks at a proposal for allowing highly efficient group exits from a pooled UTXO
- points to new coin selection strategies being proposed for Bitcoin Core
- Optech Newsletter #283 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2024/01/03/
Niklas Gögge posted to Delving Bitcoin about two vulnerabilities he had previously responsibly disclosed, which led to fixed versions of LND being released...
https://bitcoinops.org/en/newsletters/2024/01/03/#disclosure-of-past-lnd-vulnerabilities
John Law posted to the Bitcoin-Dev and Lightning-Dev mailing lists with a rough proposal for a soft fork that could allow transaction timelocks to optionally only unlock (expire) when median block feerates are below a user-chosen level...
https://bitcoinops.org/en/newsletters/2024/01/03/#fee-dependent-timelocks
Abubakar Sadiq Ismail posted to Delving Bitcoin about using some of the tools and insights from the design of cluster mempool to improve fee estimation in Bitcoin Core...
https://bitcoinops.org/en/newsletters/2024/01/03/#cluster-fee-estimation
Salvatore Ingala started a discussion on Delving Bitcoin about how to allow descriptors, particularly those for taproot, to specify a key for which no private key is known (preventing spending from that key)...
https://bitcoinops.org/en/newsletters/2024/01/03/#how-to-specify-unspendable-keys-in-descriptors
Peter Todd posted to the Bitcoin-Dev mailing list an analysis of the proposed v3 transaction relay policy on transaction pinning for contract protocols such as LN...
https://bitcoinops.org/en/newsletters/2024/01/03/#v3-transaction-pinning-costs
The SeedHammer team posted a draft BIP to the Bitcoin-Dev mailing list for including descriptors in PSBTs. The main intended use seems to be encapsulating descriptors in the PSBT format for transfer between wallets, as the proposed standard allows PSBTs to omit transaction data when a descriptor is enclosed...
https://bitcoinops.org/en/newsletters/2024/01/03/#descriptors-in-psbt-draft-bip
Johan Torås Halseth posted to Delving Bitcoin about elftrace, a proof of concept program that can use the OP_CHECKCONTRACTVERIFY opcode from the MATT soft fork proposal to allow a party in a contract protocol to claim money if an arbitrary program executed successfully...
https://bitcoinops.org/en/newsletters/2024/01/03/#verification-of-arbitrary-programs-using-proposed-opcode-from-matt
Salvatore Ingala posted to Delving Bitcoin a proposal that can improve multiparty contracts where several users share a UTXO, such as a joinpool or channel factory, and some of the users want to exit the contract at a time when other users are unresponsive (whether unintentionally or deliberately)...
https://bitcoinops.org/en/newsletters/2024/01/03/#pool-exit-payment-batching-with-delegation-using-fraud-proofs
Mark Erhardt posted to Delving Bitcoin about edge-cases users may have experienced with Bitcoin Core’s coin selection strategy and proposes two new strategies that address the edge cases by attempting to reduce the number of inputs used in wallet transactions at high feerates...
https://bitcoinops.org/en/newsletters/2024/01/03/#new-coin-selection-strategies
Bitcoin Optech will host an audio recap discussion of this newsletter with special guests Niklas Gögge, Antoine Riard, Abubakar Sadiq Ismail, Salvatore Ingala, and Gloria Zhao on Twitter Spaces Thursday at 15:00 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1YqKDgrwgONxV

2023-12-20 14:47:30

Bitcoin Optech newsletter #282: 2023 Year-in-Review Special is here:
- notes Bitcoin developments during each month of 2023
- feature: Soft fork proposals
- feature: Security disclosures
- feature: Major releases of popular infrastructure projects
- feature: Bitcoin Optech
https://bitcoinops.org/en/newsletters/2023/12/20/
This year saw much discussion and many proposals around potential soft forks...
https://bitcoinops.org/en/newsletters/2023/12/20/#softforks
Optech reported on three significant security vulnerabilities this year...
https://bitcoinops.org/en/newsletters/2023/12/20/#security
Optech covered major releases of popular infrastructure projects throughout the year...
https://bitcoinops.org/en/newsletters/2023/12/20/#releases
In Optech’s sixth year, we published 51 weekly newsletters, published a 10-part series about mempool policy, and added 15 new pages to our topics index. Optech published over 86,000 English words about Bitcoin research and development this year, the equivalent of a 250-page book.
Every newsletter this year was accompanied by a podcast episode, totaling over 50 hours in audio form and 450,000 words in transcript form with a total of 62 different guests in 2023...
https://bitcoinops.org/en/newsletters/2023/12/20/#optech
Bitcoin Optech will host an audio recap discussion of this special newsletter with special guest and Optech contributor Dave Harding on Twitter Spaces Thursday at 15:00 UTC. Join us to celebrate, discuss, or ask questions!
https://twitter.com/i/spaces/1BRJjPaAMNeKw

2023-12-13 13:26:34

Bitcoin Optech newsletter #281 is here:
- summarizes a discussion about griefing liquidity advertisements
- summarizes changes to services/client software
- summarizes popular Q&A from Stack Exchange
- Optech Newsletter #281 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2023/12/13/
Bastien Teinturier posted to the Lightning-Dev mailing list about a potential problem with timelocks on dual-funded channels created from liquidity advertisements...
https://bitcoinops.org/en/newsletters/2023/12/13/
Changes to services and client software:
- Stratum v2 mining pool launches
- Bitcoin network simulation tool warnet announced
- Payjoin client for Bitcoin Core released
- Call for community block arrival timestamps
- Envoy 1.4 released
- BBQr encoding scheme announced
- Zeus v0.8.0 released
https://bitcoinops.org/en/newsletters/2023/12/13/#changes-to-services-and-client-software
Selected Q&A from Bitcoin Stack Exchange:
- What are all the rules related to CPFP fee bumping?
- How is the total number of RBF replaced transactions calculated?
- What types of RBF exist and which one does Bitcoin Core support and use by default?
- What is the Block 1,983,702 Problem?
- What are hash functions used for in bitcoin?
https://bitcoinops.org/en/newsletters/2023/12/13/#selected-qa-from-bitcoin-stack-exchange
Bitcoin Optech will host an audio recap discussion of this newsletter with special guest Bastien Teinturier on Twitter Spaces Thursday at 15:00 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1YpJkwPgyBjJj

2023-12-06 12:53:04

Bitcoin Optech newsletter #280 is here:
- describes several discussions about the proposed cluster mempool
- summarizes the results of a test performed using warnet
- recaps the "Testing Bitcoin Core 26.0 Release Candidates" PR Review Meeting
- Bitcoin Core 26.0
- Optech Newsletter #280 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2023/12/06/
Bitcoin Core developers working on cluster mempool started a working group (WG) on the Delving Bitcoin forum. Cluster mempool is a proposal to make it much easier to operate on the mempool while respecting the required ordering of transactions...
https://bitcoinops.org/en/newsletters/2023/12/06/#cluster-mempool-discussion
Matthew Zipkin posted to Delving Bitcoin with the results of some simulations he’s run using warnet, a program that launches a large number of Bitcoin nodes with a defined set of connections between them...
https://bitcoinops.org/en/newsletters/2023/12/06/#testing-with-warnet
The 'Testing Bitcoin Core 26.0 Release Candidates' review club meeting did not review a particular PR, but rather was a group testing effort.
Before each major Bitcoin Core release, extensive testing by the community is considered essential...
https://bitcoinops.org/en/newsletters/2023/12/06/#bitcoin-core-pr-review-club
Bitcoin Core 26.0 is the next major version of the predominant full-node implementation. The release includes experimental support for the version 2 transport protocol, support for taproot in miniscript, new RPCs for working with states for assumeUTXO, and an experimental RPC for processing packages of transactions...
https://bitcoinops.org/en/newsletters/2023/12/06/#bitcoin-core-26-0
Bitcoin Optech will host an audio recap discussion of this newsletter with special guests Pieter Wuille and Matthew Zipkin on Twitter Spaces Thursday at 15:00 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1djGXNzDQRXxZ

2023-11-29 10:31:29

Bitcoin Optech newsletter #279 is here:
- summarizes an update to the liquidity advertisements specification
- summarizes popular Q&A from Stack Exchange
- Bitcoin Core 26.0rc3
- Optech Newsletter #279 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2023/11/29/
Lisa Neigut posted to the Lightning-Dev mailing list to announce an update to the specification for liquidity advertisements...
https://bitcoinops.org/en/newsletters/2023/11/29/#update-to-the-liquidity-ads-specification
Selected Q&A from Bitcoin Stack Exchange:
- Is Schnorr a multisignature interactive scheme?
- Is it advisable to operate a release candidate full node on mainnet?
- What is the relation between nLockTime and nSequence?
- What would happen if we provide to OP_CHECKMULTISIG more than threshold number (m) of signatures?
- What is “(mempool) policy”?
- What does Pay to Contract (P2C) mean?
- Can a non-segwit transaction be serialized in the segwit format?
https://bitcoinops.org/en/newsletters/2023/11/29/#selected-qa-from-bitcoin-stack-exchange
Bitcoin Core 26.0rc3 is a release candidate for the next major version of the predominant full-node implementation. There’s a testing guide available.
https://github.com/bitcoin-core/bitcoin-devwiki/wiki/26.0-Release-Candidate-Testing-Guide
Bitcoin Optech will host an audio recap discussion of this newsletter with special guest Lisa Neigut on Twitter Spaces Thursday at 15:00 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1OwGWYZdqaWxQ

2023-11-22 11:29:56

Bitcoin Optech newsletter #278 is here:
- describes a proposal to allow retrieval of LN offers using specific DNS addresses similar to lightning addresses
- summarizes changes to services/client software
- Bitcoin Core 26.0rc2 release candidate
- Optech Newsletter #278 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2023/11/22/
Bastien Teinturier posted to the Lightning-Dev mailing list about creating email-style addresses for LN users in a way that takes advantage of the features of the offers protocol...
https://bitcoinops.org/en/newsletters/2023/11/22/#offers-compatible-ln-addresses
Changes to services and client software:
- BitMask Wallet 0.6.3 released
- Opcode documentation website announced
- Athena Bitcoin adds Lightning support
- Blixt v0.6.9 released
- Durabit whitepaper announced
- BitStream whitepaper announced
- BitVM proof of concepts
- Bitkit adds taproot send support
https://bitcoinops.org/en/newsletters/2023/11/22/#changes-to-services-and-client-software
Bitcoin Core 26.0rc2 is a release candidate for the next major version of the predominant full-node implementation. There’s a testing guide available.
https://github.com/bitcoin-core/bitcoin-devwiki/wiki/26.0-Release-Candidate-Testing-Guide
Bitcoin Optech will host an audio recap discussion of this newsletter with special guests Dave Harding, Bastien Teinturier, and Robin Linus on Twitter Spaces today (Wednesday) at 15:00 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1ypKdkaaXDvxW

2023-11-15 12:34:30

Bitcoin Optech newsletter #277 is here:
- describes an update to the proposal for ephemeral anchors
- includes a contributed field report that outlines miniscript's ecosystem adoption
- provides Bitcoin Core 26.0rc2 testing materials
- Optech Newsletter #277 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2023/11/15/
Gregory Sanders posted to the Delving Bitcoin forum about a tweak to the ephemeral anchors proposal. That proposal would allow transactions to include a zero-value output with an anyone-can-spend output script...
https://bitcoinops.org/en/newsletters/2023/11/15/#eliminating-malleability-from-ephemeral-anchor-spends
Field Report: A Miniscript Journey
Antoine Poinsot from Wizardsardine describes their perspectives on miniscript adoption
https://bitcoinops.org/en/newsletters/2023/11/15/#field-report-a-miniscript-journey
Bitcoin Core 26.0rc2 is a release candidate for the next major version of the predominant full node implementation. There’s a testing guide and a scheduled meeting of the Bitcoin Core PR Review Club dedicated to testing on 15 November 2023.
https://github.com/bitcoin-core/bitcoin-devwiki/wiki/26.0-Release-Candidate-Testing-Guide
https://bitcoinops.org/en/newsletters/2023/11/15/#bitcoin-core-26-0rc2
Bitcoin Optech will host an audio recap discussion of this newsletter with special guests Dave Harding, Gregory Sanders, Antoine Poinsot, and Max Edwards on Twitter Spaces Thursday at 15:00 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1RDGlljdDeOGL

2023-11-08 12:23:47

Bitcoin Optech newsletter #276 is here:
- announces an upcoming change to the Bitcoin-Dev mailing list
- briefly summarizes a proposal to allow aggregating multiple HTLCs together
- recaps the "Fee Estimator updates from Validation Interface/CScheduler thread" PR Review Meeting
- Bitcoin Core 26.0rc2 release candidate
- Optech Newsletter #276 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2023/11/08/
Administrators for the Bitcoin-Dev mailing list announced that the organization hosting the list plans to cease hosting any mailing lists after the end of the year.
The administrators sought feedback from the community about options...
https://bitcoinops.org/en/newsletters/2023/11/08/#mailing-list-hosting
Johan Torås Halseth posted to the Lightning-Dev mailing list a suggestion for using a covenant to aggregate multiple HTLCs into a single output that could be spent all at once if a party knew all the preimages...
https://bitcoinops.org/en/newsletters/2023/11/08/#htlc-aggregation-with-covenants
'Fee Estimator updates from Validation Interface/CScheduler thread' is a PR by Abubakar Sadiq Ismail (ismaelsadeeq) that modifies the way the transaction fee estimator data is updated. It moves fee estimator updates from occurring synchronously during mempool updates to instead occur asynchronously...
https://bitcoinops.org/en/newsletters/2023/11/08/#bitcoin-core-pr-review-club
Bitcoin Core 26.0rc2 is a release candidate for the next major version of the predominant full node implementation.
There’s a scheduled meeting of the Bitcoin Core PR Review Club dedicated to testing on 15 November 2023.
https://bitcoincore.reviews/v26-rc-testing
Bitcoin Optech will host an audio recap discussion of this newsletter with special guests Johan Torås Halseth and Abubakar Ismail on Twitter Spaces Thursday at 15:00 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1gqxvQwkqOgJB

2023-11-01 11:26:32

Bitcoin Optech newsletter #275 is here:
- follows up on several recent discussions about proposed changes to Bitcoin’s scripting language
- LDK 0.0.118, Rust Bitcoin 0.31.1 releases
https://bitcoinops.org/en/newsletters/2023/11/01/
There were several replies on the Bitcoin-Dev mailing list to proposed scripting change discussions we’ve previously covered.
Anthony Towns compares Rusty
Russell’s approach to other approaches specifically for covenant-based vaults and finds it unappealing.
Several people replied to Ethan Heilman’s post announcing a proposed BIP for OP_CAT...
https://bitcoinops.org/en/newsletters/2023/11/01/#continued-discussion-about-scripting-changes
Bitcoin Optech will host an audio recap discussion of this newsletter on Twitter Spaces Thursday at 15:00 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1PlKQDwepbqxE

2023-10-25 12:57:03

Bitcoin Optech newsletter #274 is here:
- describes the replacement cycling attack against HTLCs used in LN and other systems, examines the mitigations deployed, and summarizes proposals for additional mitigations
- notes a bug affecting a Bitcoin Core RPC
- describes research into covenants with minimal changes to Bitcoin Script
- announces a proposed BIP for an OP_CAT opcode
- summarizes popular Q&A from Stack Exchange
- Optech Newsletter #274 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2023/10/25/
As briefly mentioned in last week’s newsletter, Antoine Riard posted to the Bitcoin-Dev and Lightning-Dev mailing lists about a responsibly disclosed vulnerability affecting all LN implementations.
It’s possible to use transaction replacement to remove one or more inputs of a multi-input transaction from node mempools...
https://bitcoinops.org/en/newsletters/2023/10/25/#replacement-cycling-vulnerability-against-htlcs
Several mitigations have been deployed by LN implementations for replacement cycling...
https://bitcoinops.org/en/newsletters/2023/10/25/#deployed-mitigations-in-ln-nodes-for-replacement-cycling
There have been over 40 separate posts made to the Bitcoin-Dev and Lightning-Dev mailing lists in response to the disclosure of the replacement cycling attack. Suggested responses included proposed additional mitigations...
https://bitcoinops.org/en/newsletters/2023/10/25/#proposed-additional-mitigations-for-replacement-cycling
Fabian Jahr posted to the Bitcoin-Dev mailing list to announce that a bug had been discovered in Bitcoin Core’s calculation of the hash of the current UTXO set...
https://bitcoinops.org/en/newsletters/2023/10/25/#bitcoin-utxo-set-summary-hash-replacement
Rusty Russell posted to the Bitcoin-Dev mailing list a link to some research he has performed about using a few simple new opcodes to allow a script being executed in a transaction to inspect the output scripts being paid in that same transaction, a powerful form of introspection...
https://bitcoinops.org/en/newsletters/2023/10/25/#research-into-generic-covenants-with-minimal-script-language-changes
Ethan Heilman posted to the Bitcoin-Dev mailing list a proposed BIP to add an OP_CAT opcode to tapscript...
https://bitcoinops.org/en/newsletters/2023/10/25/#proposed-bip-for-op-cat
Selected Q&A from Bitcoin Stack Exchange:
- How does the Branch and Bound coin selection algorithm work?
- Why is each transaction broadcast twice in the Bitcoin network?
- Why are OP_MUL and OP_DIV disabled in Bitcoin?
- Why are hashSequence and hashPrevouts computed separately?
- Why does Miniscript add an extra size check for hash preimage comparisons?
- How can the next block fee be less than the mempool purging fee rate?
https://bitcoinops.org/en/newsletters/2023/10/25/#selected-qa-from-bitcoin-stack-exchange
Bitcoin Core 26.0rc1 is a release candidate for the next major version of the predominant full node implementation...
https://bitcoinops.org/en/newsletters/2023/10/25/#bitcoin-core-26-0rc1
Bitcoin Optech will host an audio recap discussion of this newsletter with special guests Fabian Jahr and Ethan Heilman on Twitter Spaces Thursday at 15:00 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1rmxPMZzbYQKN

2023-10-18 12:36:39

Bitcoin Optech newsletter #273 is here:
- mentions a recent security disclosure affecting LN users
- describes a paper about making payments contingent on the result of running arbitrary programs
- announces a proposed BIP to add fields to PSBTs for MuSig2
- summarizes changes to services/client software
- Bitcoin Core 24.2rc2 and Bitcoin Core 25.1rc1 release candidates
- Optech Newsletter #273 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2023/10/18/
Antoine Riard posted to the Bitcoin-Dev and Lightning-Dev mailing lists the full disclosure of an issue he had previously responsibly disclosed to developers working on the Bitcoin protocol and various popular LN implementations...
https://bitcoinops.org/en/newsletters/2023/10/18/#security-disclosure-of-issue-affecting-ln
Robin Linus posted to the Bitcoin-Dev mailing list a paper he’s written about BitVM, a combination of methods that allows bitcoins to be paid to someone who successfully proves that an arbitrary program executed successfully. Notably, this is possible on Bitcoin today—no consensus change is required...
https://bitcoinops.org/en/newsletters/2023/10/18/#payments-contingent-on-arbitrary-computation
Andrew Chow posted to the Bitcoin-Dev mailing list with a draft BIP, partly based on prior work by Sanket Kanjalkar, for adding several fields to all versions of PSBTs for the “keys, public nonces, and partial signatures produced with MuSig2.”
https://bitcoinops.org/en/newsletters/2023/10/18/#proposed-bip-for-musig2-fields-in-psbts
Bitcoin Core 24.2rc2 and Bitcoin Core 25.1rc1 are release candidates for maintenance versions of Bitcoin Core.
https://bitcoinops.org/en/newsletters/2023/10/18/#bitcoin-core-24-2rc2
Bitcoin Optech will host an audio recap discussion of this newsletter with special guests Robin Linus and Antoine Poinsot on Twitter Spaces Thursday at 15:00 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1vAGRvZRgrvGl

2023-10-11 12:36:06

Bitcoin Optech newsletter #272 is here:
- links to a specification for a proposed OP_TXHASH opcode
- recaps the "Type-safe transaction identifiers" PR Review Meeting
- Bitcoin Core #27596 and the assumeutxo project
- Bitcoin Core #28331 and the BIP324 version 2 encrypted P2P transport project
- Optech Newsletter #272 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2023/10/11/
Steven Roose posted to the Bitcoin-Dev mailing list a draft BIP for a new OP_TXHASH opcode. The idea behind this opcode has been discussed before but this is the first specification of the idea...
https://bitcoinops.org/en/newsletters/2023/10/11/#specification-for-op-txhash-proposed
'Type-safe transaction identifiers' is a PR by Niklas Gögge (dergoegge) that improves type safety by introducing separate types for txid (the transaction identifier or hash that doesn’t include the segwit witness data) and wtxid...
https://bitcoinops.org/en/newsletters/2023/10/11/#bitcoin-core-pr-review-club
Bitcoin Core #27596 finishes the first phase of the assumeutxo project, containing all the remaining changes necessary to both use an assumedvalid snapshot chainstate and do a full validation sync in the background...
https://bitcoinops.org/en/newsletters/2023/10/11/#bitcoin-core-27596
Bitcoin Core #28331 adds support for version 2 encrypted P2P transport as specified in BIP324. The feature is currently disabled by default but can be enabled using the `-v2transport` option...
https://bitcoinops.org/en/newsletters/2023/10/11/#bitcoin-core-28331
Bitcoin Optech will host an audio recap discussion of this newsletter with special guests Steven Roose, Gloria Zhao, and James O'Beirne on Twitter Spaces Thursday at 15:00 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1nAKEamLYMgKL

2023-10-04 11:58:28

Bitcoin Optech newsletter #271 is here:
- summarizes a proposal for remotely controlling LN nodes using a hardware signing device - describes privacy-focused research and code for allowing LN forwarding nodes to dynamically split LN payments - looks at a proposal for improving LN liquidity by allowing groups of forwarding nodes to pool funds separately from their normal channels - Optech Newsletter #271 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2023/10/04/
Bastien Teinturier posted to the Lightning-Dev mailing list about a proposed BLIP that would specify how a user could send signed commands to their LN node from a hardware signing device (or any other wallet)...
https://bitcoinops.org/en/newsletters/2023/10/04/#secure-remote-control-of-ln-nodes
Gijs van Dam posted to the Lightning-Dev mailing list about a plugin he’s written for Core Lightning and some research he’s performed related to it. The plugin allows forwarding nodes to tell their peers that they support payment splitting and switching (PSS)...
https://bitcoinops.org/en/newsletters/2023/10/04/#payment-splitting-and-switching
ZmnSCPxj posted to the Lightning-Dev mailing list a suggestion for what he calls sidepools. This would involve groups of forwarding nodes working together to deposit funds in a multiparty state contract—an offchain contract (that is anchored onchain similar to an LN channel) that would allow funds to be moved between the participants by updating the offchain contract state...
https://bitcoinops.org/en/newsletters/2023/10/04/#pooled-liquidity-for-ln
Bitcoin Optech will host an audio recap discussion of this newsletter with special guest Gijs van Dam on Twitter Spaces Thursday at 15:00 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1OyKAWPldmNJb

2023-09-27 10:48:03

Bitcoin Optech newsletter #270 is here:
- describes a proposal to use covenants to significantly improve LN’s scalability
- summarizes popular Q&A from Stack Exchange
- Optech Newsletter #270 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2023/09/27/
John Law posted to the Bitcoin-Dev and Lightning-Dev mailing lists the summary of a paper he’s written about creating very large channel factories using covenants and managing the resultant channels using adaptations of several previous protocols he’s described...
https://bitcoinops.org/en/newsletters/2023/09/27/#using-covenants-to-improve-ln-scalability
Selected Q&A from Bitcoin Stack Exchange:
- How did peer discovery work in Bitcoin v0.1?
- Could reorgs cause Bitcoin to break because of the 2-hour block time restriction?
- Is there a way to download blocks from scratch without downloading block headers first?
- Where is the 21 million hard cap stated? - Are blocks containing non-standard transactions relayed through the network?
- When does Bitcoin Core allow you to “Abandon transaction”?
https://bitcoinops.org/en/newsletters/2023/09/27/#selected-qa-from-bitcoin-stack-exchange
Bitcoin Optech will host an audio recap discussion of this newsletter with special guest Anthony Towns on Twitter Spaces Thursday at 15:00 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1yNGaZaYOWbJj

2023-09-20 11:26:29

Bitcoin Optech newsletter #269 is here:
- shares the announcement of an upcoming research event
- summarizes changes to services/client software
- Optech Newsletter #269 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2023/09/20/
Sergi Delgado Segura and Clara Shikhelman posted to the Bitcoin-Dev and Lightning-Dev mailing lists to announce a Bitcoin Research Day event to be held in New York City on October 27th...
https://bitcoinops.org/en/newsletters/2023/09/20/#bitcoin-research-event
Changes to services and client software:
- Bitcoin-like Script Symbolic Trace (B’SST) released
- STARK header chain verifier demo
- JoinMarket v0.9.10 released
- BitBox adds miniscript
- Machankura announces additive batching feature
- SimLN Lightning simulation tool
https://bitcoinops.org/en/newsletters/2023/09/20/#changes-to-services-and-client-software
Bitcoin Optech will host an audio recap discussion of this newsletter with special guest Sergi Delgado Segura on Twitter Spaces Thursday at 15:00 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1OwGWYavZpkxQ?s=20

2023-09-13 12:52:49

Bitcoin Optech newsletter #268 is here:
- links to draft specifications related to taproot assets - describes a summary of several alternative message protocols for LN that can help enable the use of PTLCs - recaps the BIP324 "Transport abstraction" PR Review Meeting - adds a Client-side validation topic - Optech Newsletter #268 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2023/09/13/
Olaoluwa Osuntokun posted separately to the Bitcoin-Dev and Lightning-Dev mailing lists about the Taproot Assets client-side validation protocol. To the Bitcoin-Dev mailing list, he announced seven draft BIPs...
https://bitcoinops.org/en/newsletters/2023/09/13/#specifications-for-taproot-assets
As the first LN implementation with experimental support for channels using P2TR and MuSig2 is expected to be released soon, Greg Sanders posted to the Lightning-Dev mailing list a summary of several different previously-discussed changes to LN messages to allow them to support sending payments with PTLCs instead of HTLCs...
https://bitcoinops.org/en/newsletters/2023/09/13/#ln-messaging-changes-for-ptlcs
'Transport abstraction' is a recently-merged PR by Pieter Wuille (sipa) that introduces a transport abstraction (interface class). This PR is part of the BIP324 Version 2 P2P Encrypted Transport Protocol project...
https://bitcoinops.org/en/newsletters/2023/09/13/#bitcoin-core-pr-review-club
Client-side validation protocols allow a Bitcoin transaction to commit to some data whose validity is determined separate from the validity of the transaction under Bitcoin’s consensus rules. The client-side validation can take advantage of consensus rules, such as only allowing an output to be spent once within a valid block chain, but it may also impose additional rules known only to those interested in the validation...
https://bitcoinops.org/en/topics/client-side-validation/
Bitcoin Optech will host an audio recap discussion of this newsletter with special guests Olaoluwa Osuntokun, Greg Sanders, and Pieter Wuille on Twitter Spaces Thursday at 15:00 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1ypKddqdRLjKW

2023-09-06 13:05:20

Bitcoin Optech newsletter #267 is here:
- describes a new technique for compressing Bitcoin transactions
- summarizes an idea for privacy-enhanced transaction cosigning
- Optech Newsletter #267 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2023/09/06/
Tom Briar posted to the Bitcoin-Dev mailing list a draft specification and proposed implementation of compressed Bitcoin transactions. Smaller transactions would be more practical to relay through bandwidth constrained mediums, such as by satellite or through steganography...
https://bitcoinops.org/en/newsletters/2023/09/06/#bitcoin-transaction-compression
Nick Farrow posts to the Bitcoin-Dev mailing list about how a scriptless threshold signature scheme like FROST could improve the privacy of people who use co-signing services...
https://bitcoinops.org/en/newsletters/2023/09/06/#privacy-enhanced-co-signing
Bitcoin Optech will host an audio recap discussion of this newsletter with special guest Tom Briar on Twitter Spaces Thursday at 15:00 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1DXxyvWlwdRKM

2023-08-30 12:47:59

Bitcoin Optech newsletter #266 is here:
- announces the responsible disclosure of a vulnerability affecting old LN implementations
- summarizes a suggestion for a mashup of proposed covenant opcodes
- summarizes popular Q&A from Stack Exchange
- Optech Newsletter #266 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2023/08/30/
Matt Morehouse posted to the Lighting-Dev mailing list the summary of a vulnerability he had previously responsibly disclosed and which is now addressed in the latest versions of all popular LN implementations...
https://bitcoinops.org/en/newsletters/2023/08/30/#disclosure-of-past-ln-vulnerability-related-to-fake-funding
Brandon Black posted to the Bitcoin-Dev mailing list a proposal for a version of OP_TXHASH (see Newsletter #185) combined with OP_CHECKSIGFROMSTACK that would provide most of the features of OP_CHECKTEMPLATEVERIFY (CTV) and SIGHASH_ANYPREVOUT (APO) without much additional onchain cost over those individual proposals...
https://bitcoinops.org/en/newsletters/2023/08/30/#covenant-mashup-using-txhash-and-csfs
Selected Q&A from Bitcoin Stack Exchange:
- Is there an economic incentive to switch from P2WPKH to P2TR?
- What is the BIP324 encrypted packet structure?
- What is the false positive rate for compact block filters?
- What opcodes are part of the MATT proposal?
- Is there a well defined last Bitcoin block?
- Why are miners setting the locktime in coinbase transactions?
- Why doesn’t Bitcoin Core use auxiliary randomness when performing Schnorr signatures?
https://bitcoinops.org/en/newsletters/2023/08/30/#selected-qa-from-bitcoin-stack-exchange
Bitcoin Optech will be hosting an audio recap discussion of this newsletter with special guests Matt Corallo and Brandon Black on Twitter Spaces Thursday at 15:00 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1BRJjZmnLbaJw

2023-08-23 12:42:47

Bitcoin Optech newsletter #265 is here:
- describes fraud proofs for outdated backup state
- summarizes changes to services/client software
- adds a Peer storage topic
- Optech Newsletter #265 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2023/08/23/
Thomas Voegtlin posted to the Lightning-Dev mailing list an idea for a service that could be penalized if it provided a user with any version of the user’s backup state besides the most recent version...
https://bitcoinops.org/en/newsletters/2023/08/23/#fraud-proofs-for-outdated-backup-state
Changes to services and client software:
- Scaling Lightning call for feedback
- Torq v1.0 released
- Blixt Wallet v0.6.8 released
- Sparrow 1.7.8 released
- Open source ASIC miner bitaxeUltra prototype
- FROST software Frostsnap announced
- Libfloresta library announced
- Wasabi Wallet 2.0.4 released
https://bitcoinops.org/en/newsletters/2023/08/23/#changes-to-services-and-client-software
Peer storage is an optional service where a node accepts a small amount of frequently-updated encrypted data from its peers (especially channel counterparties)...
https://bitcoinops.org/en/topics/peer-storage/
Bitcoin Optech will be hosting an audio recap discussion of this newsletter on Twitter Spaces Thursday at 15:00 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1OyKAVLllOwGb

2023-08-17 19:47:07

Earlier today Mark “Murch” Erhardt and Mike Schmidt spoke with Brandon Black and Dan Gould in a Bitcoin privacy-focused recap including:
- Silent Payments
- Payjoins
- MuSig2
- Eclipse attacks
- BIP324
Catchup here:
https://bitcoinops.org/en/podcast/2023/08/17/

2023-08-16 13:06:10

Bitcoin Optech newsletter #264 is here:
- summarizes a discussion about adding expiration dates to silent payment addresses
- provides an overview of a draft BIP for serverless payjoin
- includes a contributed field report that describes the implementation and deployment of a MuSig2-based wallet for scriptless multisignatures
- Optech Newsletter #264 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2023/08/16/
Peter Todd posted to the Bitcoin-Dev mailing list a recommendation to add a user-chosen expiration date to addresses for silent payments...
https://bitcoinops.org/en/newsletters/2023/08/16/#adding-expiration-metadata-to-silent-payment-addresses
Dan Gould posted to the Bitcoin-Dev mailing list a draft BIP for serverless payjoin...
https://bitcoinops.org/en/newsletters/2023/08/16/#serverless-payjoin
Field Report: Implementing MuSig2
Brandon Black from BitGo describes their perspectives on integrating MuSig2 in their wallet for scriptless multisignatures...
https://bitcoinops.org/en/newsletters/2023/08/16/#field-report-implementing-musig2
Bitcoin Optech will be hosting an audio recap discussion of this newsletter with special guests Brandon Black and Dan Gould on Twitter Spaces Thursday at 15:00 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1LyGBqgdXVjKN

2023-08-11 10:37:01

Yesterday we were joined by Dave Harding and spoke about HTLC endorsement with Clara Shikhelman, proposed changes to Bitcoin Core default relay policy with Peter Todd, silent payments with Josie Baker and more
Catchup here:
https://bitcoinops.org/en/podcast/2023/08/10/

2023-08-09 16:18:15

Bitcoin Optech newsletter #263 is here:
- warns about a vulnerability in uses of Libbitcoin’s bx tool
- summarizes discussion about the design of DoS protection
- announces a plan to begin testing and collecting data about HTLC endorsement
- describes two proposed changes to Bitcoin Core’s tx relay policy
- recaps the "Silent Payments: Implement BIP352" PR Review Meeting
- Adds Topics for: Codex32, HTLC endorsement
- Optech Newsletter #263 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2023/08/09/
Severe Libbitcoin Bitcoin Explorer vulnerability: if you used the bx seed command to create BIP32 seeds, BIP39 mnemonics, private keys, or any other secure material, consider immediately moving any funds to a different secure address...
https://bitcoinops.org/en/newsletters/2023/08/09/#severe-libbitcoin-bitcoin-explorer-vulnerability
Anthony Towns posted to the Lightning-Dev mailing list in response to the channel jamming part of the notes for the recent LN developers meeting. Towns suggested an alternative to trying to price out attackers...
https://bitcoinops.org/en/newsletters/2023/08/09/#denial-of-service-dos-protection-design-philosophy
Carla Kirk-Cohen and Clara Shikhelman posted to the Lightning-Dev mailing list to announce that developers associated with Eclair, Core Lightning, and LND were implementing parts of the HTLC endorsement protocol in order to begin collecting data related to it...
https://bitcoinops.org/en/newsletters/2023/08/09/#htlc-endorsement-testing-and-data-collection
Peter Todd started two threads on the Bitcoin-Dev mailing list related to pull requests he’s opened to change Bitcoin Core’s default relay policy...
https://bitcoinops.org/en/newsletters/2023/08/09/#proposed-changes-to-bitcoin-core-default-relay-policy
Several security researchers investigating a recent loss of bitcoins among users of Libbitcoin discovered that program’s Bitcoin Explorer (bx) tool’s seed command only generated about 4 billion different unique values...
https://bitcoinops.org/en/newsletters/2023/08/09/#libbitcoin-bitcoin-explorer-security-disclosure
‘Silent Payments: Implement BIP352’ is a PR by josibake that takes the first step in adding silent payments to the Bitcoin Core wallet...
https://bitcoinops.org/en/newsletters/2023/08/09/#bitcoin-core-pr-review-club
Codex32 is an encoding designed for BIP32 seeds that is convenient to store on paper. It supports relatively simple processes for creating a seed, encoding that seed, splitting the seed into parts, and verifying the integrity of partial or full seed backups...
https://bitcoinops.org/en/topics/codex32/
HTLC endorsement is a reputation system proposed for LN. When a node receives a payment (HTLC) from a channel counterparty for forwarding, that payment may be flagged as endorsed...
https://bitcoinops.org/en/topics/htlc-endorsement/
Bitcoin Optech will be hosting an audio recap discussion of this newsletter with special guests Clara Shikhelman, Josie Baker, and Peter Todd on Twitter Spaces Thursday at 15:00 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1RDGlayOZDRJL

2023-08-02 12:41:47

Bitcoin Optech newsletter #262 is here:
- links to transcripts of recent LN specification meetings
- summarizes a thread about the safety of blind MuSig2 signing
- Optech Newsletter #262 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2023/08/02/
Carla Kirk-Cohen posted to the Lightning-Dev mailing list to announce that the last several video conference meetings to discuss changes to the LN specification were transcribed...
https://bitcoinops.org/en/newsletters/2023/08/02/#transcripts-of-periodic-ln-specification-meetings
Tom Trevethan posted to the Bitcoin-Dev mailing list to request a review of a cryptographic protocol planned as part of a statechains deployment. The goal was to deploy a service that would use its private key to create a MuSig2 partial signature without gaining any knowledge about what it was signing or how its partial signature was used...
https://bitcoinops.org/en/newsletters/2023/08/02/#safety-of-blind-musig2-signing
Bitcoin Optech will be hosting an audio recap discussion of this newsletter on Twitter Spaces Thursday at 15:00 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1eaJbrgAlWqJX

2023-07-26 13:03:49

Bitcoin Optech newsletter #261 is here:
- describes a protocol for simplifying the communication related to mutual closing of LN channels
- summarizes notes from a recent meeting of LN developers
- summarizes popular Q&A from Stack Exchange
- Adds Topics for: Channel announcements, Cluster mempool, Redundant overpayments
- Optech Newsletter #261 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2023/07/26/
Rusty Russell posted to the Lightning-Dev mailing list a proposal that simplifies the process of two LN nodes mutually closing a channel they share...
https://bitcoinops.org/en/newsletters/2023/07/26/#simplified-ln-closing-protocol
Carla Kirk-Cohen posted to the Lightning-Dev mailing list a summary of several discussions from the recent meeting of LN developers in New York City...
https://bitcoinops.org/en/newsletters/2023/07/26/#ln-summit-notes
Selected Q&A from Bitcoin Stack Exchange:
- How can I manually (on paper) calculate a Bitcoin public key from a private key?
- Why are there 17 native segwit versions?
- Does 0 OP_CSV force the spending transaction to signal BIP125 replaceability?
- How do route hints affect pathfinding?
- What does it mean that the security of 256-bit ECDSA, and therefore Bitcoin keys, is 128 bits?
https://bitcoinops.org/en/newsletters/2023/07/26/#selected-qa-from-bitcoin-stack-exchange
Channel announcements are advertisements that a channel is available to forward payments. The advertisements are relayed through the LN gossip network...
https://bitcoinops.org/en/topics/channel-announcements/
Cluster mempool is a proposal to associate each unconfirmed transaction in a mempool with related transactions, creating a cluster. Each cluster of transactions, whether it be a single transaction or several transactions, can be ordered from most desirable to mine to least desirable, allowing operations for adding or removing new clusters to complete fast enough to use them in P2P network code...
https://bitcoinops.org/en/topics/cluster-mempool/
Redundant overpayments are LN payments split into parts where the spender sends a greater amount and more parts than necessary to pay the receiver’s invoice.
Even if some of the parts fail to arrive at the receiver’s node on the first try due to forwarding failures, enough of the other parts may arrive to allow the receiver to claim their invoiced amount...
https://bitcoinops.org/en/topics/redundant-overpayments/
Bitcoin Optech will be hosting an audio recap discussion of this newsletter with special guests Greg Sanders and Bastien Teinturier on Twitter Spaces Thursday at 15:00 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1DXGyvjzgXNJM

2023-07-19 12:23:10

Bitcoin Optech newsletter #260 is here:
- includes 'Waiting for confirmation #10: Get Involved' from our series about policies for transaction relay and mempool inclusion
- summarizes changes to services/client software
- Optech Newsletter #260 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2023/07/19/
Waiting for confirmation #10: Get Involved
We hope this series has given readers a better idea of what’s going on while they are waiting for confirmation. We started with a discussion about how some of the ideological values of Bitcoin translate to its structure and design goals. The distributed structure of the peer-to-peer network offers increased censorship resistance and privacy over a typical centralized model...
https://bitcoinops.org/en/newsletters/2023/07/19/#waiting-for-confirmation-10-get-involved
Changes to services and client software:
- Wallet 10101 beta testing pooling funds between LN and DLCs
- LDK Node announced
- Payjoin SDK announced
- Validating Lightning Signer (VLS) beta announced
- BitGo adds MuSig2 support
- Peach adds RBF support
- Phoenix wallet adds splicing support
- Mining Development Kit call for feedback
- Binance adds Lightning support
- Nunchuk adds CPFP support
https://bitcoinops.org/en/newsletters/2023/07/19/#changes-to-services-and-client-software
Bitcoin Optech will be hosting an audio recap discussion of this newsletter with special guest Gloria Zhao on Twitter Spaces Thursday at 15:00 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1OdKrzzpmLkKX

2023-07-12 13:05:09

Bitcoin Optech newsletter #259 is here:
- describes a proposal to remove details from the LN specification that are no longer relevant to modern nodes
- includes 'Waiting for confirmation #9: Policy Proposals' from our series about policies for transaction relay and mempool inclusion
- recaps the "Stop relaying non-mempool txs" PR Review Meeting
- Optech Newsletter #259 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2023/07/12/
Rusty Russell posted to the Lightning-Dev mailing list a link to a PR where he proposes to remove some features that are no longer supported by modern LN implementations and to assume other features will always be supported...
https://bitcoinops.org/en/newsletters/2023/07/12/#ln-specification-clean-up-proposed
Waiting for confirmation #9: Policy Proposals
Last week’s post described anchor outputs and CPFP carve out, ensuring either channel party can fee-bump their shared commitment transactions without requiring collaboration. This approach still contains a few drawbacks. This post explores current efforts to address these and other limitations...
https://bitcoinops.org/en/newsletters/2023/07/12/#waiting-for-confirmation-9-policy-proposals
'Stop relaying non-mempool txs' is a PR by Marco Falke (MarcoFalke) that simplifies the Bitcoin Core client by removing an in-memory data structure, mapRelay, that may cause high memory consumption and is no longer needed...
https://bitcoinops.org/en/newsletters/2023/07/12/#bitcoin-core-pr-review-club
Bitcoin Optech will be hosting an audio recap discussion of this newsletter with special guests Gloria Zhao, Bastien Teinturier, and Martin Zumsande on Twitter Spaces Thursday at 15:00 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1YqxoAAYQEBGv

2023-07-05 12:54:33

Bitcoin Optech newsletter #258 is here:
- includes 'Waiting for confirmation #8: Policy as an Interface' from our series about policies for transaction relay and mempool inclusion
- Core Lightning 23.05.2
- Optech Newsletter #258 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2023/07/05/
Waiting for confirmation #8: Policy as an Interface
Since transaction relay policy changes to Bitcoin Core can impact whether an application’s transactions relay, they require socialization with the wider Bitcoin community prior to consideration. Similarly, applications and second layer protocols that utilize transaction relay must be designed with policy rules in mind to avoid creating transactions that are rejected...
https://bitcoinops.org/en/newsletters/2023/07/05/#waiting-for-confirmation-8-policy-as-an-interface
Bitcoin Optech will be hosting an audio recap discussion of this newsletter with special guest Gloria Zhao on Twitter Spaces Thursday at 15:00 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1gqGvylbbrqKB

2023-06-28 12:38:20

Bitcoin Optech newsletter #257 is here:
- summarizes an idea for preventing the pinning of coinjoin transactions
- describes a proposal for speculatively using hoped-for consensus changes
- includes 'Waiting for confirmation #7: Network Resources' from our series about policies for transaction relay and mempool inclusion
- summarizes popular Q&A from Stack Exchange
- Optech Newsletter #257 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2023/06/28/
Greg Sanders posted to the Bitcoin-Dev mailing list a description for how the proposed v3 transaction relay rules could allow creating a coinjoin-style multiparty transaction that wouldn’t be vulnerable to transaction pinning...
https://bitcoinops.org/en/newsletters/2023/06/28/#preventing-coinjoin-pinning-with-v3-transaction-relay
Robin Linus posted to the Bitcoin-Dev mailing list an idea for spending money to a script fragment that can’t be executed for a long time (such as 20 years). If that script fragment is interpreted under current consensus rules, it will allow miners in 20 years to claim all the funds paid to it...
https://bitcoinops.org/en/newsletters/2023/06/28/#speculatively-using-hoped-for-consensus-changes
Waiting for confirmation #7: Network Resources
A previous post discussed protecting node resources, which may be unique to each node and thus sometimes configurable. We also made our case for why it is best to converge on one policy, but what should be part of that policy? This post will discuss the concept of network-wide resources, critical to things like scalability, upgradeability and accessibility of bootstrapping and maintaining a full node...
https://bitcoinops.org/en/newsletters/2023/06/28/#waiting-for-confirmation-7-network-resources
Selected Q&A from Bitcoin Stack Exchange:
- Why do Bitcoin nodes accept blocks that have so many excluded transactions?
- Why does everyone say that soft forks restrict the existing ruleset?
- Why is the default LN channel limit set to 16777215 sats?
- Why does Bitcoin Core use ancestor score instead of just ancestor fee rate to select transactions?
- How does Lightning multipart payments (MPP) protocol define the amounts per part?
https://bitcoinops.org/en/newsletters/2023/06/28/#selected-qa-from-bitcoin-stack-exchange
Bitcoin Optech will be hosting an audio recap discussion of this newsletter with special guests Gloria Zhao, Greg Sanders, and Robin Linus on Twitter Spaces Thursday at 15:00 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1OdJrzVXdEwJX

2023-06-21 12:15:00

Bitcoin Optech newsletter #256 is here:
- summarizes a discussion about extending BOLT11 invoices to request two payments
- includes 'Waiting for confirmation #6: Policy Consistency' from our series about policies for transaction relay and mempool inclusion
- summarizes changes to services/client software
- add Submarine swaps and Just-In-Time (JIT) channels topics
- Optech Newsletter #256 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2023/06/21/
Thomas Voegtlin posted to the Lightning-Dev mailing list to suggest BOLT11 invoices be extended to optionally allow a receiver to request two separate payments from a spender, with each payment having a separate secret and amount...
https://bitcoinops.org/en/newsletters/2023/06/21/#proposal-to-extend-bolt11-invoices-to-request-two-payments
Waiting for confirmation #6: Policy Consistency
Last week’s introduced policy, a set of transaction validation rules applied in addition to consensus rules. These rules are not applied to transactions in blocks, so a node can still stay in consensus even if its policy differs from that of its peers. Just like a node operator may decide to not participate in transaction relay, they are also free to choose any policy, up to none at all...
https://bitcoinops.org/en/newsletters/2023/06/21/#waiting-for-confirmation-6-policy-consistency
Changes to services and client software:
- Greenlight libraries open sourced
- Tapscript debugger Tapsim
- Bitcoin Keeper 1.0.4 announced
- Lightning wallet EttaWallet announced
- zkSNARK-based block header sync PoC announced
- lnprototest v0.0.4 released
https://bitcoinops.org/en/newsletters/2023/06/21/#changes-to-services-and-client-software
Submarine swaps are trust-minimized atomic swaps of offchain bitcoins for onchain bitcoins. A payment secured by an HTLC is routed over LN to a service provider who creates an onchain output paying the same HTLC...
https://bitcoinops.org/en/topics/submarine-swaps/
JIT channels are virtual LN channels hosted by a service provider. When the first payment to the channel is received, the service provider creates a funding transaction and adds the payment to it, creating a normal channel...
https://bitcoinops.org/en/topics/jit-channels/
Bitcoin Optech will be hosting an audio recap discussion of this newsletter with special guest Thomas Voegtlin on Twitter Spaces Thursday at 15:00 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1djxXloOldkxZ

2023-06-14 13:55:59

Bitcoin Optech newsletter #255 is here:
- summarizes discussion about allowing relay of txs containing taproot annex data
- links to a silent payments draft BIP
- includes 'Waiting for confirmation #5: Policy for Protection of Node Resources' from our series about policies for transaction relay and mempool inclusion
- recaps the "Allow inbound whitebind connections to more aggressively evict peers when slots are full" PR Review Meeting
- #255 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2023/06/14/
Joost Jager posted to the Bitcoin-Dev mailing list a request for a change in the Bitcoin Core transaction relay and mining policy to allow storing arbitrary data in the taproot annex field...
https://bitcoinops.org/en/newsletters/2023/06/14/#discussion-about-the-taproot-annex
Josie Baker and Ruben Somsen posted to the Bitcoin-Dev mailing list a draft BIP for silent payments, a type of reusable payment code that will produce a unique onchain address each time it is used, preventing output linking...
https://bitcoinops.org/en/newsletters/2023/06/14/#draft-bip-for-silent-payments
Waiting for confirmation #5: Policy for Protection of Node Resources
A node that fully validates blocks and transactions requires resources including memory, computational resources, and network bandwidth. We must keep resource requirements low in order to make running a node accessible and to defend the node against exploitation...
https://bitcoinops.org/en/newsletters/2023/06/14/#waiting-for-confirmation-5-policy-for-protection-of-node-resources
Allow inbound whitebind connections to more aggressively evict peers when slots are full is a PR by Matthew Zipkin (pinheadmz) that improves a node operator’s ability in certain cases to configure desired peers for the node...
https://bitcoinops.org/en/newsletters/2023/06/14/#bitcoin-core-pr-review-club
Bitcoin Optech will be hosting an audio recap discussion of this newsletter with special guests Gloria Zhao, Joost Jager, Josie Baker, Ruben Somsen, and Matthew Zipkin on Twitter Spaces Thursday at 15:00 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1ynKOaqgqOWJR

2023-06-08 15:01:21

Join Optech on Twitter Spaces in 2 hours (1500 UTC) where we will chat MATT/OP_CTV/joinpools, mempools and transaction feerates, and more with Dave Harding, Gloria Zhao, Johan Torås Halseth and Salvatore Ingala
https://twitter.com/i/spaces/1rmxPkAqDwDJN

2023-06-07 13:05:22

- reply

Bitcoin Optech will be hosting an audio recap discussion of this newsletter with special guests Dave Harding, Gloria Zhao, Johan Torås Halseth and Salvatore Ingala on Twitter Spaces Thursday at 15:00 UTC. Join us to discuss or ask questions!
https://twitter.com/i/spaces/1rmxPkAqDwDJN

2023-06-07 13:05:00

- reply

Waiting for confirmation #4: Feerate estimation
Last week, we explored techniques for minimizing the fees paid on a transaction given a feerate. But what should that feerate be? Ideally, as low as possible to save money, but high enough to secure a spot in a block suitable for the user’s time preference.
The goal of fee(rate) estimation is to translate a target timeframe for confirmation to a minimal feerate the transaction should pay...
https://bitcoinops.org/en/newsletters/2023/06/07/#waiting-for-confirmation-4-feerate-estimation

2023-06-07 13:04:42

- reply

Johan Torås Halseth posted to the Bitcoin-Dev mailing list about using the OP_CHECKOUTPUTCONTRACTVERIFY opcode (COCV) from the Merklize All The Things (MATT) proposal to replicate the functionality of the OP_CHECKTEMPLATEVERIFY proposal.
https://bitcoinops.org/en/newsletters/2023/06/07/#using-matt-to-replicate-ctv-and-manage-joinpools

2023-06-07 13:04:20

Bitcoin Optech newsletter #254 is here:
- summarizes mailing list discussion about using the MATT proposal to manage joinpools and replicate functions of the OP_CHECKTEMPLATEVERIFY proposal
- includes 'Waiting for confirmation #4: Feerate estimation' from our series about policies for transaction relay and mempool inclusion
- Optech Newsletter #254 Recap on Twitter Spaces
https://bitcoinops.org/en/newsletters/2023/06/07/

2023-06-02 17:16:52

Hello, nostr!