This week’s newsletter summarizes posts to the Bitcoin-Dev mailing list about payjoin adoption and making hardware wallets compatible with more advanced Bitcoin features. Also included are our regular sections with overviews of changes to services and client software, new releases and release candidates, and changes to popular Bitcoin infrastructure software.

News

  • ● Payjoin adoption: Chris Belcher posted to the Bitcoin-Dev mailing list a request for people to look for ways to increase payjoin adoption along with a wiki page tracking the projects that provide either sending or receiving support for payjoin. One suggestion by Craig Raw was to extend the protocol to allow it to work even when the receiver doesn’t operate a server.

  • ● Making hardware wallets compatible with more advanced Bitcoin features: Kevin Loaec started a discussion on the Bitcoin-Dev mailing list about how hardware wallets could be changed to allow them to handle scripts more complicated than single-sig or multisig. For example, allowing a hardware wallet to handle in-channel LN payments or payments made from a vault. His post does a good job of describing various problems that current hardware wallets can’t handle, but he notes that necessary “changes may be very difficult”.

Changes to services and client software

In this monthly feature, we highlight interesting updates to Bitcoin wallets and services.

  • ● Blockstream announces Jade hardware wallet: Blockstream’s new Jade hardware wallet is open source, supports Bitcoin and Liquid networks, and is compatible with Blockstream Green for Android.

  • ● Coldcard adds payjoin signing: Coldcard’s 3.2.1 release adds BIP78 payjoin signing support and various multisig improvements.

  • ● Mempool v2.0.0 released: Open source block explorer mempool, which backs the mempool.space website, has released version 2.0.0. Mempool supports Bitcoin Core, Electrum, and Esplora backends and also exposes block, transaction, and address information via APIs.

  • ● BlueWallet adds multisig: Version 6.0.0 of BlueWallet adds the ability to create and manage air-gapped, native segwit multisig vaults.

  • ● Sparrow supports connecting to Bitcoin Core: Sparrow 0.9.10, using Bitcoin Wallet Tracker v0.2.1’s Java Native Interface bindings feature, now supports connecting directly to a backing Bitcoin Core node.

Releases and release candidates

New releases and release candidates for popular Bitcoin infrastructure projects. Please consider upgrading to new releases or helping to test release candidates.

Notable code and documentation changes

Notable changes this week in Bitcoin Core, C-Lightning, Eclair, LND, Rust-Lightning, libsecp256k1, Hardware Wallet Interface (HWI), Rust Bitcoin, BTCPay Server, Bitcoin Improvement Proposals (BIPs), and Lightning BOLTs.

  • ● Bitcoin Core #19937 adds a new standalone bitcoin-util executable and miner script for mining signet blocks, making it easier to create and maintain new signet networks. Also included is extensive documentation for the new tools.

  • ● LND #4917 disables the use of anchor outputs by default, a feature that was planned to be released in the upcoming 0.12.0-beta. Advanced users can still opt-in to using anchors. The commit messages notes that, “the plan is to enable anchors by default [in a later release].”

  • ● Rust-Lightning #742 improves the signer API by providing per-transaction information necessary for the signer to perform additional checks and provide a signature. This PR is part of a larger effort to support external signers in Rust-Lightning tracked here.

  • ● BTCPay Server #2169 adds functions that provide support for decoding output script descriptors referring to wallets created following BIPs 44 (P2PKH HD wallets), 45 (P2SH multisig HD wallets), 49 (P2SH-P2WPKH HD wallets), 84 (native P2WPKH HD wallets), and a proposed amendment to BIP44 for other multisig derivations (which has undocumented extensions for the use of P2SH-P2WSH and native P2WSH).