schmidty

bitcoin

Moonsettler and Julian joined Optech to discuss Newsletter #383:

- A consensus bug in the NBitcoin library found with differential fuzzing
- LNHANCE soft fork proposal updates
- Benchmarking Bitcoin Script under the proposed varops budget
- Optimizations to SLH-DSA (SPHINCS) post-quantum signatures
- And More

You can listen on our website:
https://bitcoinops.org/en/podcast/2025/12/09/ 

Fountain:
https://fountain.fm/episode/hWoSXyZivt2VIK3sD2m5 

Spotify:
https://open.spotify.com/episode/7xoG5U9JOs579CkQhc1G58 

Apple Podcasts:
https://podcasts.apple.com/us/podcast/bitcoin-optech-newsletter-383-recap/id1674626983?i=1000740473439 

LNHANCE, varops, post-quantum - Bitcoin Optech Newsletter #383 Recap Podcast

Bitcoin Optech newsletter #383 is here:

- describes a fixed vulnerability affecting the NBitcoin library
- summarizes the LNHANCE soft fork proposal
- relays a call to action to benchmark Bitcoin script execution under GSR's varops budget
- highlights discussion of optimizations to SLH-DSA (SPHINCS) post-quantum signatures
- Optech Newsletter #383 Podcast
https://bitcoinops.org/en/newsletters/2025/12/05/

Bruno Garcia posted to Delving Bitcoin about a theoretical consensus failure in NBitcoin that could occur when using OP_NIP...
https://bitcoinops.org/en/newsletters/2025/12/05/#consensus-bug-in-nbitcoin-library

Moonsettler proposes a soft fork for LNHANCE now that all four of its constituent opcodes have updated BIPs and reference implementations...
https://bitcoinops.org/en/newsletters/2025/12/05/#lnhance-soft-fork

Julian posted a call to action to benchmark Bitcoin script execution under the varops budget...
https://bitcoinops.org/en/newsletters/2025/12/05/#benchmarking-the-varops-budget

Continuing the discussions around hardening Bitcoin against quantum computing, conduition presented his work on optimizing the SPHINCS signing algorithm...
https://bitcoinops.org/en/newsletters/2025/12/05/#slh-dsa-sphincs-post-quantum-signature-optimizations

Bitcoin Optech will host an audio recap discussion of this newsletter on Riverside.fm Tuesday at 17:30 UTC. Join us to discuss or ask questions!
https://riverside.fm/studio/bitcoin-optech


Changing consensus - Bitcoin Optech Newsletter #383

Mark “Murch” Erhardt, Gustavo Flores Echaiz, and Mike Schmidt discuss Newsletter #382:

- Updated stats on compact block reconstructions
- A motion to activate BIP3 and replace the current BIP process
- 3 questions from the Bitcoin Stack Exchange
- And more

You can listen on our website:
https://bitcoinops.org/en/podcast/2025/12/02/

Fountain:
https://fountain.fm/episode/93Jhx6LCQCiZDKQYppJ8

Spotify:
https://open.spotify.com/episode/3RlXvoyRoZW5Rw1u3GcsIM

Apple Podcasts:
https://podcasts.apple.com/us/podcast/bitcoin-optech-newsletter-382-recap/id1674626983?i=1000739533949

Compact blocks, BIP3, Q&A - Bitcoin Optech Newsletter #382 Recap Podcast

Bitcoin Optech newsletter #382 is here:

- provides an update on compact block reconstruction discussions
- relays a call to activate BIP3
- summarizes popular Q&A from Stack Exchange
- Optech Newsletter #382 Podcast
https://bitcoinops.org/en/newsletters/2025/11/28/

0xB10C posted an update to Delving Bitcoin about his statistics around compact block reconstruction...
https://bitcoinops.org/en/newsletters/2025/11/28/#stats-on-compact-block-reconstructions-updates

Murch posted to the Bitcoin-Dev mailing list a formal motion to activate BIP3...
https://bitcoinops.org/en/newsletters/2025/11/28/#motion-to-activate-bip3

Selected Q&A from Bitcoin Stack Exchange:
- Do pruned nodes store witness inscriptions?
- Increasing probability of block hash collisions when difficulty is too high
- What is the purpose of the initial 0x04 byte in all extended public and private keys?
https://bitcoinops.org/en/newsletters/2025/11/28/#selected-qa-from-bitcoin-stack-exchange

Bitcoin Optech will host an audio recap discussion of this newsletter on Riverside.fm Tuesday at 17:30 UTC. Join us to discuss or ask questions!
https://riverside.fm/studio/bitcoin-optech

Compact blocks, BIP3, Stack Exchange - Bitcoin Optech Newsletter #382

We published Brink's annual financial and organizational report for the community. Feedback and questions welcome.

Brink’s 2024 Annual Financial Report

Antoine Poinsot and ZmnSCPxj joined Optech to discuss Newsletter #381:

- Modeling stale rates by propagation delay and mining centralization
- Private key handover for collaborative closure
- Updates to services and client software
- And more

You can listen on our website:
https://bitcoinops.org/en/podcast/2025/11/25/

Fountain:
https://fountain.fm/episode/3zDWx0jj8JOTj9ukAoC6

Spotify:
https://open.spotify.com/episode/0BsoRU9mZZiLLlDYFtLo0W

Apple Podcasts:
https://podcasts.apple.com/us/podcast/bitcoin-optech-newsletter-381-recap/id1674626983?i=1000738423632

Antoine Poinsot and ZmnSCPxj - Bitcoin Optech Newsletter #381 Recap Podcast

Block propagation & miner revenue, resolving multi-party protocols - Optech #381

Bitcoin Optech newsletter #381 is here:

- looks at an analysis of how block propagation times may affect miner revenue
- describes a new approach for resolving protocols where multiple parties share funds
- summarizes changes to services/client software
- Optech Newsletter #381 Podcast
https://bitcoinops.org/en/newsletters/2025/11/21/

Antoine Poinsot posted to Delving Bitcoin about modeling stale block rates and how block propagation time affects a miner’s revenue as a function of its hashrate...
https://bitcoinops.org/en/newsletters/2025/11/21/#modeling-stale-rates-by-propagation-delay-and-mining-centralization

ZmnSCPxj posted to Delving Bitcoin about private key handover, an optimization that protocols can implement when funds, previously owned by two parties, need to be refunded to a single entity...
https://bitcoinops.org/en/newsletters/2025/11/21/#private-key-handover-for-collaborative-closure

Changes to services and client software:
- Arkade launches
- Mempool monitoring mobile application
- Web-based policy and miniscript IDE
- Phoenix Wallet adds taproot channels
- Nunchuk 2.0 launches
- LN gossip traffic analysis tool announced
https://bitcoinops.org/en/newsletters/2025/11/21/#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

TheCharlatan joined Optech to discuss Newsletter #380:

- The Bitcoin Kernel
- And more

You can listen on our website:
https://bitcoinops.org/en/podcast/2025/11/18/

Fountain:
https://fountain.fm/episode/Qmqqq6fCDHTZt1SL0xxi

Spotify:
https://open.spotify.com/episode/5qGvgMkll7x3KQviU8Vm65

Apple Podcasts:
https://podcasts.apple.com/us/podcast/bitcoin-optech-newsletter-380-recap/id1674626983?i=1000737307431

Bitcoin Optech Newsletter #380 Recap Podcast


As part of Brink's mission to ensure the safety and robustness of the open-source Bitcoin Core software, we recently sponsored an independent security audit of the Bitcoin Core codebase.

This represents the first public, third-party audit of Bitcoin Core.
https://brink.dev/blog/2025/11/19/bitcoin-core-security-audit/

The assessment was conducted by Quarkslab and was coordinated with the help of the Open Source Technology Improvement Fund (OSTIF). Funding was provided by Brink with the support of our donors, with technical collaboration from Brink engineer, Niklas Gögge, and Chaincode Labs engineer, Antoine Poinsot.

Why Brink funded this work

The project has a strong security track record, but it has never undergone an external security assessment. We wanted to provide an additional layer of assurance for developers, node operators, holders, and businesses who rely on Bitcoin Core every day

What the audit involved

The focus was on the most security-critical components of the software, including the peer-to-peer networking layer, mempool, chain management, and consensus logic and included:

- Manual code review
- Static and dynamic analysis
- Advanced fuzz testing

What the auditors found

The auditors at Quarkslab reported no critical, high, or medium-severity issues. They identified two low-severity findings and thirteen informational recommendations, none of which were classified as security vulnerabilities under Bitcoin Core’s criteria.

Funding independent reviews like this is just one way we help ensure Bitcoin doesn’t break and continues to serve the world as a secure, reliable monetary network.

Independent review only strengthens that confidence.

Thank you to Quarkslab, the OSTIF, Niklas, and Antoine for their work on this project.

The full report is publicly available here: 
https://ostif.org/wp-content/uploads/2025/11/25-05-2133-REP-bitcoincore-security-assessment-V1.3.pdf

An Independent Security Audit of Bitcoin Core

Bitcoin Optech newsletter #380 is here:

- LND 0.20.0-beta.rc4
- libbitcoinkernel's C header API
- Optech Newsletter #380 Podcast
https://bitcoinops.org/en/newsletters/2025/11/14/

LND 0.20.0-beta.rc4 is a release candidate for a new version of this popular LN node implementation that introduces multiple bug fixes, a new noopAdd HTLC type, support for P2TR fallback addresses on BOLT11 invoices, and many RPC and lncli additions and improvements...
https://bitcoinops.org/en/newsletters/2025/11/14/#lnd-0-20-0-beta-rc4

Bitcoin Core #30595 introduces a C header that serves as an API for libbitcoinkernel, enabling external projects to interface with Bitcoin Core’s block validation and chainstate logic via a reusable C library...
https://bitcoinops.org/en/newsletters/2025/11/14/#bitcoin-core-30595

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 #380

Sebastian Falbesoner, PortlandHODL, Tadge Dryja, and Antoine Poinsot joined Optech to discuss Newsletter #379: 

- ECDSA signature validation in OpenSSL vs. libsecp256k1
- Multiple discussions about restricting data
- Post-quantum signature aggregation
- Native STARK proof verification in Bitcoin Script
- BIP54 implementation and test vectors
- And more

You can listen on our website:
https://bitcoinops.org/en/podcast/2025/11/11/

Fountain:
https://fountain.fm/episode/6cQbKPDwMKQ2qu4HA14r

Spotify:
https://open.spotify.com/episode/26JrUei66sLjcgXHMzmsTU

Apple Podcasts:
https://podcasts.apple.com/us/podcast/bitcoin-optech-newsletter-379-recap/id1674626983?i=1000736447881

Bitcoin Optech Newsletter #379 Recap Podcast

Bitcoin Optech newsletter #379 is here:

- shares an analysis comparing the historical performance of the OpenSSL and libsecp256k1 libraries
- highlights multiple discussions about restricting data
- summarizes a proposed post-quantum signature aggregation opcode
- summarizes an idea for STARK proof verification in Bitcoin Script
- updates progress on BIP54's consensus cleanup
- Optech Newsletter #379 Podcast
https://bitcoinops.org/en/newsletters/2025/11/07/

Sebastian Falbesoner posted to Delving about comparing the performance of ECDSA signature validation between OpenSSL and libsecp256k1 over the last decade...
https://bitcoinops.org/en/newsletters/2025/11/07/#comparing-performance-of-ecdsa-signature-validation-in-openssl-vs-libsecp256k1

Multiple conversations examined ideas to change the limits of various fields in consensus...
https://bitcoinops.org/en/newsletters/2025/11/07/#multiple-discussions-about-restricting-data

Tadge Dryja posted to the Bitcoin-Dev mailing list a proposal for an OP_CHECKINPUTVERIFY (OP_CIV) opcode that enables a locking script to commit to a specific UTXO being spent in the same transaction...
https://bitcoinops.org/en/newsletters/2025/11/07/#post-quantum-signature-aggregation

Abdelhamid Bakhta posted to Delving Bitcoin a detailed proposal for a new tapscript opcode OP_STARK_VERIFY which would enable the verification of a specific variant of STARK proof in Bitcoin Script...
https://bitcoinops.org/en/newsletters/2025/11/07/#native-stark-proof-verification-in-bitcoin-script

Antoine Poinsot posted to the Bitcoin-Dev mailing list an update on his consensus cleanup work on BIP54...
https://bitcoinops.org/en/newsletters/2025/11/07/#bip54-implementation-and-test-vectors

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 #379

Where is the public roadmap for Bitcoin Core?

I think when people are asking for a roadmap, they are really just asking for some more visibility in to whats going on. In the case of Bitcoin Core, there is actually a ton of visibility (see my OP), but what is really missing is translating that transparent activity into something understandable by less-technical folks.

Good thing there is no roadmap! See the OP

I'd agree on any sort of formal roadmap.

I hope that people can use those sources of information I pointed to, to come to their own conclusions.

“Where is the public roadmap for Bitcoin Core?”

This sentiment from Zach is common and Ill give my own thoughts on it
https://x.com/zachherbert/status/1976726178376696016 

The subprojects that individual Bitcoin Core engineers contribute to reflect the project’s *software development priorities* which can include things like testing improvements, refactors, features, maintenance, or performance improvements.

These software engineering efforts are distinct from the Bitcoin *protocol*, whose consensus rules change only through broad community agreement and network adoption, not by decisions made exclusively within the Bitcoin Core repository.

If I were looking to derive a shorter term “public roadmap for Bitcoin Core” (again, the Bitcoin Core software, not Bitcoin protocol), there are a few places to look.

**Working Groups**

Contributors actively working on similar efforts form working groups to implement and review projects in Bitcoin Core. A list of the current working groups is on the Bitcoin Core Wiki:
https://github.com/bitcoin-core/bitcoin-devwiki/wiki/Working-Groups#current-working-groups 

From here we can see interest in: Erlay, Fuzzing, Kernel, Benchmarking, Silent Payments, Cluster Mempool, Stratum v2, Multiprocess, QML GUI, and Net Split

These working groups also provide updates at the weekly Bitcoin Core developer meetings on IRC: https://bitcoincore.org/en/meetings/ This is another place to see current work.

**Tracking issues**

Many subprojects within Bitcoin Core have a place to track a todo list of code changes that roll up into that project.

Here are just a few examples (search the GitHub for “tracking issue” for more):

Multiprocess - https://github.com/bitcoin/bitcoin/issues/28722 
Mining interface - https://github.com/bitcoin/bitcoin/issues/33777 
MuSig2 - https://github.com/bitcoin/bitcoin/issues/31246 
Cluster mempool - https://github.com/bitcoin/bitcoin/issues/30289 
Erlay - https://github.com/bitcoin/bitcoin/issues/30249 
Bitcoin Kernel Library - https://github.com/bitcoin/bitcoin/issues/27587 
SENDTEMPLATE - https://github.com/bitcoin/bitcoin/issues/33691 

**Core Dev meetups**

What developers discuss at recent in-person meetings is another data point. Here are transcripts from the
October 2025 meeting - https://btctranscripts.com/bitcoin-core-dev-tech/2025-10 
February 2025 meeting - https://btctranscripts.com/bitcoin-core-dev-tech/2025-02 

**Merged PRs**

As code changes are merged into the Bitcoin Core GitHub before the next release you can see precisely what will be in the upcoming release. These code changes include PRs related to projects above, but also more general changes unrelated to a particular project, like maintenance work, additional testing, one-off features, etc.

https://github.com/bitcoin/bitcoin/pulls?q=is%3Apr+is%3Amerged

Likewise Optech has a weekly notable code segment that picks interesting code merges to cover: https://bitcoinops.org/

**Release Milestones**

As Bitcoin Core progresses toward a new release, PRs can be tagged with a milestone representing that release.

For example, here are the items tagged for the previous v30 release:
https://github.com/bitcoin/bitcoin/pulls?q=is%3Apr+milestone%3A30.0 

And here are considerations for the v31 release: https://github.com/bitcoin/bitcoin/pulls?q=is%3Apr+milestone%3A31.0

**TLDR, just tell me what will be in v31**

Sorry, there isn’t a definitive authoritative answer for a decentralized open source project like this. But also in the spirit of decentralization, I can provide my own guesses of what might be in there.

Kernel API - modular use of Bitcoin’s consensus and validation logic outside the full node

MuSig2 (in wallet) - fee-efficient, privacy-preserving multi-signature support

Cluster mempool - makes transaction relay and block assembly more efficient, predictable, and network reliability.

ASMap - help diversify peer connections, strengthening network resilience against eclipse attacks

Static builds - reproducible, portable binaries that enhance security, verifiability, and ease of deployment

I’ll emphasize that while these projects took a ton of work to get where they are, there will also be a majority of PRs in v31 that will not be part of a “project”. They will simply be general improvements, bug fixes, and maintenance work (see https://x.com/bitschmidty/status/1976692672023667057 for examples)


Mark “Murch” Erhardt and Mike Schmidt discuss Newsletter #378:

- Disclosure of four low-severity vulnerabilities in Bitcoin Core
- Q&A from Bitcoin Stack Exchange including questions on datacarriersize, OP_TEMPLATEHASH and others
- And more

You can listen on our website:
https://bitcoinops.org/en/podcast/2025/11/04/

Fountain:
https://fountain.fm/episode/52iLDnzzU5I7rxb8coJT 

Spotify:
https://open.spotify.com/episode/3gvj03rHM7qT0jTnQcMnfH

Apple Podcasts:
https://podcasts.apple.com/us/podcast/bitcoin-optech-newsletter-378-recap/id1674626983?i=1000735256317

Bitcoin Optech Newsletter #378 Recap Podcast

Bitcoin Core Developer Event - Frankfurt, Germany

I like the fuzz testing and security work really coming along. I think everyone is sleeping on Bitcoin Kernel. Cluster Mempool is coming although probably more under the covers than anything.

Transcript are up

https://btctranscripts.com/bitcoin-core-dev-tech/2025-10

Last week many Bitcoin Core developers met up in Frankfurt, Germany as part of their regular twice-yearly in person meetings.

Attendees volunteered to take notes on the unconference-style sessions and I have a pull request to add the notes to the BTC transcripts website:

- ASMap
- Batch Validation
- Secp256k1 and quantum
- CISA
- Cluster mempool
- CMake
- CoreCheck
- Debugging
- Fuzzamoto
- Libsha
- Multiprocess and Mining Interface
- Fingerprinting
- Net / net_processing split
- Package relay
- Private broadcast
- Security audit
- Subject matter experts and working groups
- Sockets abstraction

Additional informal discussions, code reviews, working groups, or other sessions occurred on:

- BIP 3
- Wallet priorities
- Compact Block prefills
- Silent Payments
- btck
- CI
- SwiftSync
- Benchmarking and IBD
- When do Bitcoin Core users upgrade?
- MuSig2
- Kernel
- Working in-person
- Complications with fuzz testing
- BlockTemplateManager
- QML GUI
- Shared Templates BIP
- Headers-first sync
- Batch Validation
- FIBRE
- Consensus Cleanup
- Silent payments libsecp256k1 light client
- Better communicating with the broad community
- Discussion on block 920138 and Bitcoin Core #33687
- Mempool and relay policy
- CI with CTest and CDash

This meeting was sponsored by BTrust who provided the funding for the venue, food, supplies, etc to facilitate the meeting (thank you!).

JD (from localhost research), Emily (from Brink) and myself organized.

A list of previous meetings is here: https://coredev.tech

The PR to the http://btctranscripts.com website is open here, pending approval:
https://github.com/bitcointranscripts/bitcointranscripts/pull/593