V3 bitcoin transactions!



Version 3 transaction relay is a proposal to allow transactions to opt-in to a modified set of transaction relay policies designed to prevent pinning attacks. Combined with package relay, these policies help enable the use of dynamic feerates with LN onchain transactions.

Project tracking


Credit: glowzow

Securing a $100MM Lightning node


After years of R&D on how to secure our Lightning node, we have settled on a combination of AWS Nitro Enclaves (an Isolated Compute Environment) and Ledger Nano (a signing device with a trusted display). This setup offers what we believe is the best trade-off between security, flexibility, performance, and operational complexity for running a professional Lightning node.

Phoenix deploys splicing!


TL; DR: Splicing changes the game. Phoenix now manages a single dynamic channel, no more 1% fee on inbound liquidity, better predictability and control, trustless swaps. The new fee schedule is detailed here.

Wallet Scrutiny



The WalletScrutiny team is a small, non-profit collection of privacy and security-focused engineers helping everyone from bitcoin newcomers to full-fledged cypherpunks make informed decisions about how they store and send their bitcoin. So it’s only fitting to be as transparent about ourselves as we encourage wallet developers to be.

A Technical Walkthrough of Hash Time Locked Contracts and Lightning Channel Operations


Credit: Elle Mouton

This post will walk through the different operations of a Lightning channel by following a long-running example with plenty of explanatory diagrams. First, we explore how Hash Time Locked Contracts (HTLCs) are added to a channel and how channel peers commit to a new state including these HTLCs. Next, we discuss how a channel’s normal flow is re-established after a disconnection. And finally, we finish with how a cooperative channel closure happens.

New ECDSA cryptanalysis


Credit: Dylan Rowe, Joachim Breitner, and Nadia Heninger

This paper describes a cryptanalytic attack that allows for secret key recovery when observing ECDSA signatures that use a certain kind of structured nonce. Using the standard deterministic nonce construction avoids this attack.