schmidty

bitcoin

Bitcoin Optech Newsletter #368 is here:

- summarizes a draft BIP for block template sharing between full nodes
- announces a library that allows trusted delegation of script evaluation
- summarizes changes to services/client software
- Optech Newsletter #368 Podcast
https://bitcoinops.org/en/newsletters/2025/08/22/

Anthony Towns posted to the Bitcoin-Dev mailing list the draft of a BIP for how nodes can communicate to their peers the transactions they would attempt to mine in their next block...
https://bitcoinops.org/en/newsletters/2025/08/22/#draft-bip-for-block-template-sharing

Josh Doman posted to Delving Bitcoin about a library he’s written that uses a trusted execution environment (TEE) that will only sign a taproot keypath spend if the transaction containing that spend satisfies a script...
https://bitcoinops.org/en/newsletters/2025/08/22/#trusted-delegation-of-script-evaluation

Changes to services and client software:
- ZEUS v0.11.3 released
- Rust Utreexo resources
- Peer-observer tooling and call to action
- Bitcoin Core Kernel-based node announced
- SimplicityHL released
- LSP plugin for BTCPay Server
- Proto mining hardware and software announced
- Oracle resolution demo using CSFS
- Relai adds taproot support
https://bitcoinops.org/en/newsletters/2025/08/22/#changes-to-services-and-client-software

Bitcoin Optech will host an audio recap discussion of this newsletter on Riverside.fm Tuesday at 16:30 UTC. Join us to discuss or ask questions!
https://riverside.fm/studio/bitcoin-optech

Bitcoin Optech Newsletter #368

Mark “Murch” Erhardt and Mike Schmidt discussed Newsletter #367:

- Removing peer discouragement for consensus-invalid transactions
- A per-input cache for sighash pre-computation to the script interpreter
- And more

You can listen on our website:
https://bitcoinops.org/en/podcast/2025/08/19/

Fountain:
https://fountain.fm/episode/rDxi7POxEBQhwV26KwsQ

Spotify:
https://open.spotify.com/episode/5BrkPRC5Yob7j0aPHegngv

Apple Podcasts:
https://podcasts.apple.com/us/podcast/bitcoin-optech-newsletter-367-recap/id1674626983?i=1000722685501 

Bitcoin Optech Newsletter #367 Recap Podcast


Bitcoin Optech Newsletter #367 is here:

- LND v0.19.3-beta.rc1
- Bitcoin Core 29.1rc1
- Optech Newsletter #367 Podcast

Bitcoin Optech will host an audio recap discussion of this newsletter on Riverside.fm Tuesday at 16:30 UTC. Join us to discuss or ask questions!
https://riverside.fm/studio/bitcoin-optech


Bitcoin Optech Newsletter #367

Bitcoin Optech Newsletter #366 Recap Podcast

You can listen on our website:
https://bitcoinops.org/en/podcast/2025/08/12/

Fountain:
https://fountain.fm/episode/mb22hz065ESbbtqZvMy6

Spotify:
https://open.spotify.com/episode/58sQEBHrZ5Z22iUID6x5Je

Apple Podcasts:
https://podcasts.apple.com/us/podcast/bitcoin-optech-newsletter-366-recap/id1674626983?i=1000721833977

Gloria Zhao and Mike Schmidt were joined by Tadge Dryja and Anthony Towns to discuss Newsletter #366:

- Draft BIPs proposed for Utreexo
- Continued discussion about lowering the minimum relay feerate 
- Peer block template sharing to mitigate problems with divergent mempool policies
- A watch only wallet PR Review Club
- And more

Bitcoin Optech newsletter #366 is here:

- announces draft BIPs for Utreexo
- summarizes continued discussion about lowering the minimum transaction relay feerate
- describes a proposal to allow nodes to share their block templates to mitigate problems with divergent mempool policies
- recaps the "Add exportwatchonlywallet RPC to export a watchonly version of a wallet" PR Review Meeting
- includes a recommendation to readers
- issues a correction to last week’s newsletter
- Optech Newsletter #366 Podcast

Calvin Kim posted to the Bitcoin-Dev mailing list to announce three draft BIPs co-authored by him along with Tadge Dryja and Davidson Souza about the Utreexo validation model...
https://bitcoinops.org/en/newsletters/2025/08/08/#draft-bips-proposed-for-utreexo

Gloria Zhao posted to Delving Bitcoin about lowering the default minimum relay feerate by 90% to 0.1 sat/vbyte...
https://bitcoinops.org/en/newsletters/2025/08/08/#continued-discussion-about-lowering-the-minimum-relay-feerate

Anthony Towns posted to Delving Bitcoin to suggest full node peers occasionally send each other their current template for the next block using compact block relay encoding...
https://bitcoinops.org/en/newsletters/2025/08/08/#peer-block-template-sharing-to-mitigate-problems-with-divergent-mempool-policies

Add exportwatchonlywallet RPC to export a watchonly version of a wallet is a PR by achow101 that reduces the amount of manual work required to create a watch-only wallet...
https://bitcoinops.org/en/newsletters/2025/08/08/#bitcoin-core-pr-review-club

Bitcoin++ Insider has begun publishing reader-funded news about technical Bitcoin topics. Two of their free weekly newsletters, Last Week in Bitcoin and This Week in Bitcoin Core, may be especially interesting to regular readers of the Optech newsletter...
https://bitcoinops.org/en/newsletters/2025/08/08/#optech-recommends

In last week’s newsletter, we incorrectly described the updated version of BIP360, pay to quantum-resistant hash, as “making exactly the change” that Tim Ruffing showed was secure in his recent paper...
https://bitcoinops.org/en/newsletters/2025/08/08/#correction

Bitcoin Optech will host an audio recap discussion of this newsletter on Riverside.fm Tuesday at 16:30 UTC. Join us to discuss or ask questions!
https://riverside.fm/studio/bitcoin-optech

Bitcoin Optech Newsletter #366

Russell O’Connor joined Brink engineers to explain his work on formal verification of software, the process of mathematically proving that a program satisfies its specification.

- Overview of formal verification of software
- Walkthrough w/ libsecp256k1
- Coq, Rocq, Clightgen
- SafeGCD
- Q&A

Russell O'Connor on formal verification and libsecp256k1

David Gumberg, Lauren Shareshian, Jameson Lopp, Steven Roose, and Tim Ruffing joined Optech to discuss Newsletter #365:

- Compact block prefilling 
- Mempool-based fee estimation
- Migration from quantum-vulnerable outputs 
- The OP_TEMPLATEHASH proposal 
- Proposal to allow longer relative timelocks
- Security against quantum computers with taproot as a commitment scheme 
- And more


Bitcoin Optech Newsletter #365 Recap Podcast

Bitcoin Optech newsletter #365 is here:

- summarizes the results of a test of compact block relay prefilling
- links to a mempool-based fee estimation library
- migration from quantum-vulnerable outputs
- taproot-native OP_TEMPLATEHASH proposal
- proposal to allow longer relative timelocks
- security against quantum computers with taproot as a commitment scheme
- Optech Newsletter #365 Podcast
https://bitcoinops.org/en/newsletters/2025/08/01/

David Gumberg replied to a Delving Bitcoin thread about compact block reconstruction efficiency with a summary of the results he obtained testing compact block relay prefilling—a node pre-emptively relaying some or all transactions in a new block to its peers when it thinks the peers may not already have those transactions...
https://bitcoinops.org/en/newsletters/2025/08/01/#testing-compact-block-prefilling

Lauren Shareshian posted to Delving Bitcoin to announce a library for fee estimation developed by Block...
https://bitcoinops.org/en/newsletters/2025/08/01/#mempool-based-fee-estimation-library

Jameson Lopp posted to the Bitcoin-Dev mailing list a three-step proposal for phasing out spending from quantum-vulnerable outputs...
https://bitcoinops.org/en/newsletters/2025/08/01/#migration-from-quantum-vulnerable-outputs

Greg Sanders posted to Bitcoin-Dev mailing list a proposal to add three opcodes to tapscript...
https://bitcoinops.org/en/newsletters/2025/08/01/#taproot-native-op-templatehash-proposal

Developer Pyth posted to Delving Bitcoin to suggest allowing BIP68 relative timelocks to be extended from their current maximum of about one year to a new maximum of about ten years...
https://bitcoinops.org/en/newsletters/2025/08/01/#proposal-to-allow-longer-relative-timelocks

Tim Ruffing posted a link to a paper he wrote analyzing the security of taproot commitments against manipulation by quantum computers...
https://bitcoinops.org/en/newsletters/2025/08/01/#security-against-quantum-computers-with-taproot-as-a-commitment-scheme

Bitcoin Optech will host an audio recap discussion of this newsletter on Riverside.fm Tuesday at 16:30 UTC. Join us to discuss or ask questions!
https://riverside.fm/studio/bitcoin-optech

Bitcoin Optech Newsletter #365

Matt Morehouse and Jesse Posner joined Optech to discuss Newsletter #364:

- LND gossip filter DoS vulnerability 
- Chain code withholding for multisig scripts 
- Research indicates common Bitcoin primitives are compatible with quantum-resistant signature algorithms 
- Stack Exchange Q&A
- And More

Fountain:
https://fountain.fm/episode/tQ7DBX3FTiiAzp6Sp0aD

Spotify:
https://open.spotify.com/episode/6nQ1pe8K4UAizGYslBD6HX

Apple Podcasts:
https://podcasts.apple.com/us/podcast/bitcoin-optech-newsletter-364-recap/id1674626983?i=1000720103505


Bitcoin Optech Newsletter #364 Recap Podcast

Brink is seeking a motivated intern, remote or in London, to join our team and contribute to Bitcoin security through fuzzing, working under the mentorship of experienced team members.



Bitcoin Core Fuzzing Internship @ Brink

Bitcoin Optech newsletter #364 is here:

- summarizes a vulnerability affecting old versions of LND
- describes an idea for improving privacy when using co-signer services
- examines the impact of switching to quantum-resistant signature algorithms on HD wallets, scriptless multisig, and silent payments
- summarizes popular Q&A from Stack Exchange
- Optech Newsletter #364 Recap

Matt Morehouse posted to Delving Bitcoin about a vulnerability affecting past versions of LND that he previously responsibly disclosed...
https://bitcoinops.org/en/newsletters/2025/07/25/#lnd-gossip-filter-dos-vulnerability

Jurvis Tan posted to Delving Bitcoin about research he performed with Jesse Posner into improving the privacy and security of multisig collaborative custody...
https://bitcoinops.org/en/newsletters/2025/07/25/#chain-code-withholding-for-multisig-scripts

Jesse Posner posted to Delving Bitcoin several links to research papers that indicate that quantum-resistant signature algorithms provide comparable primitives to those currently used in Bitcoin...
https://bitcoinops.org/en/newsletters/2025/07/25/#research-indicates-common-bitcoin-primitives-are-compatible-with-quantum-resistant-signature-algorithms

Selected Q&A from Bitcoin Stack Exchange:
- How does Bitcoin Core handle reorgs larger than 10 blocks?
- Advantages of a signing device over an encrypted drive?
- Spending a taproot output through the keypath and scriptpath? 
https://bitcoinops.org/en/newsletters/2025/07/25/#selected-qa-from-bitcoin-stack-exchange

Bitcoin Optech will host an audio recap discussion of this newsletter on Riverside.fm Tuesday at 16:30 UTC. Join us to discuss or ask questions!
https://riverside.fm/studio/bitcoin-optech

Bitcoin Optech Newsletter #364

Davidson Souza joined Optech discuss Newsletter #363:
- Utreexo node Floresta
- The RGB v0.12 announcement
- A FROST signing device
- Gemini adding taproot support
- Electrum 4.6.0 release

https://bitcoinops.org/en/podcast/2025/07/22/

Bitcoin Optech Newsletter #363 Recap Podcast

Bitcoin Optech newsletter #363 is here:

- summarizes changes to services/client software including Floresta, RGB, Frostsnap and more
- LND v0.19.2-beta
- Optech Newsletter #363 Recap

Changes to services and client software:
- Floresta v0.8.0 released
- RGB v0.12 announced
- FROST signing device available
- Gemini adds taproot support
- Electrum 4.6.0 released

Bitcoin Optech will host an audio recap discussion of this newsletter on Riverside.fm Tuesday at 16:30 UTC. Join us to discuss or ask questions! https://riverside.fm/studio/bitcoin-optech

Bitcoin Optech Newsletter #363

Josh Doman and Gloria Zhao joined Optech to discuss ⁠⁠Newsletter #362⁠⁠:

- Compressing script descriptors
- A PR review club about orphans in Bitcoin Core
- And our usual releases and notable code segments



Bitcoin Optech Newsletter #362 Recap Podcast

Bitcoin Optech newsletter #362 is here:

- briefly describes a new library allowing output script descriptors to be compressed for use in QR codes
- recaps the "Improve TxOrphanage denial of service bounds" PR Review Meeting
- #362 Recap Podcast
https://bitcoinops.org/en/newsletters/2025/07/11/

Josh Doman posted to Delving Bitcoin to announce a library he’s written that encodes output script descriptors into a binary format that reduces their size by about 40%...
https://bitcoinops.org/en/newsletters/2025/07/11/#compressed-descriptors

Improve TxOrphanage denial of service bounds is a PR by glozow that changes TxOrphanage eviction logic to guarantee each peer the resources for at least 1 maximum-size package worth of orphan resolution...
https://bitcoinops.org/en/newsletters/2025/07/11/#bitcoin-core-pr-review-club

Bitcoin Optech will host an audio recap discussion of this newsletter on Riverside.fm Tuesday at 16:30 UTC. Join us to discuss or ask questions!
https://riverside.fm/studio/bitcoin-optech

Bitcoin Optech Newsletter #362

Sanket Kanjalkar, Jonas Nick, Tadge Dryja, Steven Roose, and Brandon Black joined Optech this week to discuss:

- A new onion message network
- CTV+CSFS and benefits to PTLCs and BitVM
- Vault descriptors
- The CTV and CSFS open letter
- Winternitz signatures using OP_CAT
- Commit/reveal function for post-quantum recovery
- OP_TXHASH variant with support for transaction sponsorship
- And more

https://bitcoinops.org/en/podcast/2025/07/08/

Bitcoin Optech Newsletter #361 Recap Podcast

Bitcoin Optech newsletter #361 is here:

- describes a proposal to separate the network connections and peer management used for onion message relay from those used for HTLC relay in LN
- CTV+CSFS advantages for PTLCs
- Vault output script descriptor
- Continued discussion about CTV+CSFS advantages for BitVM
- Open letter about CTV and CSFS
- OP_CAT enables Winternitz signatures
- Commit/reveal function for post-quantum recovery
- OP_TXHASH variant with support for transaction sponsorship
- Optech Newsletter #361 Recap Podcast
https://bitcoinops.org/en/newsletters/2025/07/04/

Olaluwa Osuntokun posted to Delving Bitcoin about allowing nodes to use separate connections for relaying onion messages than they use for relaying HTLCs...
https://bitcoinops.org/en/newsletters/2025/07/04/#separating-onion-message-relay-from-htlc-relay

Developers continued a previous discussion about the benefits of OP_CHECKTEMPLATEVERIFY (CTV), OP_CHECKSIGFROMSTACK (CSFS), or both together for various deployed and imagined protocols...
https://bitcoinops.org/en/newsletters/2025/07/04/#ctv-csfs-advantages-for-ptlcs

Sjors Provoost posted to Delving Bitcoin to discuss how the recovery information for a wallet using vaults could be specified using an output script descriptor...
https://bitcoinops.org/en/newsletters/2025/07/04/#vault-output-script-descriptor

Developers continued the previous discussion about how the availability of OP_CHECKTEMPLATEVERIFY (CTV) and OP_CHECKSIGFROMSTACK (CSFS) opcodes could “reduce [BitVM] transaction sizes by approximately 10x” and allow non-interactive peg-ins...
https://bitcoinops.org/en/newsletters/2025/07/04/#continued-discussion-about-ctv-csfs-advantages-for-bitvm

James O’Beirne posted an open letter to the Bitcoin-Dev mailing signed by 66 individuals (as of this writing), many of them contributors to Bitcoin-related projects...
https://bitcoinops.org/en/newsletters/2025/07/04/#open-letter-about-ctv-and-csfs

Developer Conduition posted to the Bitcoin-Dev mailing list a prototype implementation that uses the proposed OP_CAT opcode and other Script instructions to allow quantum-resistant signatures using the Winternitz protocol to be verified by consensus logic...
https://bitcoinops.org/en/newsletters/2025/07/04/#op-cat-enables-winternitz-signatures

Tadge Dryja posted to the Bitcoin-Dev mailing list a method for allowing individuals to spend UTXOs using quantum-vulnerable signature algorithms even if fast quantum computers would otherwise allow redirecting (stealing) the output of any attempted spend...
https://bitcoinops.org/en/newsletters/2025/07/04/#commit-reveal-function-for-post-quantum-recovery

Steven Roose posted to Delving Bitcoin about a variation on OP_TXHASH called TXSIGHASH that extends 64-byte schnorr signatures with additional bytes to indicate what fields in the transaction (or related transactions) the signature commits to...
https://bitcoinops.org/en/newsletters/2025/07/04/#op-txhash-variant-with-support-for-transaction-sponsorship

Bitcoin Optech will host an audio recap discussion of this newsletter on Riverside.fm Tuesday at 16:30 UTC. Join us to discuss or ask questions!
https://riverside.fm/studio/bitcoin-optech

Changing Consensus - Bitcoin Optech Newsletter #361

Daniela Brozzoni and Naiyoma joined Murch and Schmidty to discuss Newsletter #360:

- Fingerprinting Bitcoin Core nodes
- Descriptors and BIP380
- Questions from the bitcoin stack exchange about blocking knots nodes, OP_CAT, compact blocks, selfish mining
- And more

https://bitcoinops.org/en/podcast/2025/07/01/

Bitcoin Optech Newsletter #360 Recap Podcast

Bitcoin Optech Newsletter #360

Join us!

We have timestamps on the show pages to find what you like and skip around.

A week or so after publication we also have transcripts if you prefer to read or search.

Bitcoin Optech newsletter #360 is here:

- summarizes research about fingerprinting full nodes using P2P protocol messages
- seeks feedback about possibly removing support for H in BIP32 paths in the BIP380 specification of descriptors
- summarizes popular Q&A from Stack Exchange
- Optech Newsletter #360 Recap Podcast
https://bitcoinops.org/en/newsletters/2025/06/27/

Daniela Brozzoni posted to Delving Bitcoin about research she conducted with developer Naiyoma into identifying the same node on multiple networks using the addr messages it sends...
https://bitcoinops.org/en/newsletters/2025/06/27/#fingerprinting-nodes-using-addr-messages

Ava Chow posted to the Bitcoin-Dev mailing list to ask whether any software generates descriptors using uppercase-H to indicate a hardened BIP32 key derivation step...
https://bitcoinops.org/en/newsletters/2025/06/27/#does-any-software-use-h-in-descriptors

Selected Q&A from Bitcoin Stack Exchange:

- Is there any way to block Bitcoin Knots nodes as my peers?
- What does OP_CAT do with integers?
- Async Block Relaying With Compact Block Relay (BIP152) 
- Why is attacker revenue in selfish mining disproportional to its hash-power?
https://bitcoinops.org/en/newsletters/2025/06/27/#selected-qa-from-bitcoin-stack-exchange

Bitcoin Optech will host an audio recap discussion of this newsletter on Riverside.fm Tuesday at 16:30 UTC. Join to discuss or ask questions!
https://riverside.fm/studio/bitcoin-optech
