We will start with introductions, some basic ground rules, and jump into technical discussions. We will cover aspects of the bitcoin protocol, new research developments, recent news, and software developments.

Please note the meeting location at 4801 Glenwood Ave suite 200 in Raleigh, right above Fifth Third Bank.


  • no pictures or recordings
  • chatham house rules
  • don’t be a dick
  • Hack Day - unstructured monthly in-person meetup for bitcoin builders
  • thank you to our sponsor Lolli
  • introductions


Mastering Bitcoin 3rd Edition

Mastering Bitcoin is the quintessential guide for understanding bitcoin at a technical level. In the 3rd Edition, coauthored by David Harding, it receives a much needed update to include missing topics both old and new. All technologies that went into taproot are described, as well as a rewritten address section, fee management, compact blocks, soft fork activation methods, client-side validation protocols, and too many other awesome things to list them all. You should stop reading this and go put it in your shopping cart already.

bitcoin-dev Mailing List is Moving

In this bitcoin-dev mailing list post, Bryan Bishop discusses why the mailing list needs to move and the possible future home for this community. The mailing list has moved before from Sourceforge.net to the Linux Foundation. Bishop discusses the importance of decentralized archiving using a service called “Public Inbox” which can be hosted by anyone and invites the community to offer feedback and propose solutions.

Bitcoin Core’s Development Priorities in 2023

In this article Triangle BitDevs host vnprc writes about a new strategy initiative for Bitcoin Core in 2023. A group of core developers have agreed to prioritize a short list of “big rock” projects that are both highly impactful and difficult to get merged. With two of the four big rocks merged into master in the last month it seems like this initiative has been very successful!


Timeout Trees

Mailing list contributor John Law proposes a new way to batch open lightning channels using a simple covenant (CTV or APO) from a lightning service provider with a timeout expiration. This design allows the LSP to open a large number of channels for their users in a single on-chain transaction. Near the end of the channel’s life the users can simply drain their channel balance into a new channel opened with a timeout tree. Bitcoin Magazine contributor Shinobi published a more accessible treatment of the topic here.

Replacement Cycling Attack

Bitcoin and Lightning protocol researcher Antoine Riard dropped a new lightning attack on the mailing list. The attack requires two malicious LN nodes on either side of a routing node to withhold the HTLC preimage from the victim node and continually replace the victim’s channel close transaction in the mempool until the timelock expires. Every LN node implementation has implemented fixes to mitigate the attack, but there is currently no way to completely eliminate the risk. SatsBridge has published an article explaining the attack with lots of helpful diagrams.


Payjoin Receive in Mutiny Wallet

Dan Gould has opened a draft PR to add payjoin receive to Mutiny Wallet. This exciting development has the potential to improve the best lightning privacy wallet with payjoin, an opportunistic privacy technique that obfuscates the on-chain transaction graph with every payment.


Durabit: A Bitcoin-native Incentive Mechanism for Data Distribution

Some guy released a white paper describing Durabit, an incentive-compatible decentralized solution to the data availability problem. It uses a bitcoin bond to reward participants for seeding a bittorrent file. The protocol relies on two distinct parties to accomplish this: the bond issuer creates a series of presigned CSV timelocked bitcoin transactions payable to a chaumian ecash mint, which is in charge of compensating torrent seeders using the bond funds. The bond issuer encodes the bittorrent magnet link into an OP_RETURN output and is capable of revoking the bond by double spending the next presigned transaction. Not only is the author an anonymous nym, but they dropped the whitepaper via an ordinal inscription. Cypherpunk af. 🤘

Opcode Explained

Opcode Explained is a new site by BDK contributor Thunderbiscuit that explains every opcode. Or aims to, it is 80% complete. You can expect to see many more links to this site from ours in the future!