Hi Insiders. This is Tuma, open-source reporter from the Insider Edition.

In this week update we feature the current effort from the LDK team to add support for recurrent payments in BOLT12. We also discuss a new plugin for Core-lightning to rebalance channels in a node.

We also cover the most interesting news from the Bitcoin ecosystem. Notably, we talk about Iceberg, a new nested threshold MuSig2 signature scheme, that allows Lightning operators to thresholdize one participant inside a multi-signature protocol.

#

Highlights from the bitcoin developer ecosystem

I spent 10+ hours in open-source developer calls in the Bitcoin ecosystem last week. Here is what caught my eye:

• The LDK team is working to introduce recurrent payments in BOLT12.

  • During the biweekly call, on Monday 17th, LDK contributors discussed PR4882 in rust-lightning which aims to introduce recurrent payments int BOLT12.
  • PR4882 is implementing the protocol flow and all the primitives needed for recurring payments to work. On the other hand, recurrence tracking, persistence, and scheduling will be handled downstream — For example in LDK Node.
  • The implementation of recurrent payments is going hand in hand with the drafting of the specification in the BOLT repository. Specifically, LN contributors are working on PR1240.

• A plugin for Core-lightning for rebalancing channels in a node.

  • During the biweekly call, on Monday 17th, Core Lightning developers discussed a new plugin to rebalance channels called xrebalance , develoeped by the main CLBOSS maintainer Ken Sedgwick.
  • Rebalancing is done through independent circular self-payments between different channels on the same node, leveraging the askrene plugin for improved routing computation.
  • The plugin is still experimental and under active development, and works out-of-the-box with CLN versions v26.04 or higher.

---

A BIPs Update

In the last days there was some movement in the BIP repository. Specifically, one new BIP has been assigned a number by BIP maintainer Murchandamus.

Numbered BIPs#

A list of BIPs that recently got assigned a number

BIP332: Stale Tip Relay#

Assigned On: Aug 20th, 2026

Layer: Peer Services

PR2241 introduces BIP 332, which defines a new, opt-in P2P message called staletip whose goal is to announce recent stale chain tips to peers. The message contains the block height at which a stale branch diverges (the fork point), a vector containing the block headers belonging to the stale branch, and a flag signaling willingness to serve that block data. This may be useful for monitoring the network health, since increases in the stale block rate may expose validation or relay bottlenecks, network partitions, or selfish mining behavior.

---

Other News from the Bitcoin World

• Iceberg, a multisig for managing Lightning channels: Paul Gerhart, Nadav Kohen, Jesse Posner, and Matias Furszyfer published a paper presenting a new cryptographic primitive, nested threshold multi-signatures, which allows to thresholdize one participant inside a multi-signature protocol.

  • As a first implementation of this scheme, the group presented Iceberg, the first construction for nested threshold MuSig2 signatures. It enables one side of a Lightning channel to operate as a t-of-nthreshold group while appearing to the counterparty as a standard MuSig2 participant.
  • The proposed scheme can be used today, without any modification neither to the Bitcoin protocol, nor to Lightning.

• New major version for Coco: The Cashu team announced that a new major version — v2.0.0 — for Coco had been released.

  • Coco is a TypeScript library that provides the easiest way to develop Cashu-based wallets or integrate the ecash protocol in various applications.
  • The latest version brings the library up-to-date with the latest developments in the Cashu ecosystem. It implements minting and melting operations through BOLT12 (NUT-25) and on-chain payments (NUT-30), payment requests based on NUT-18, and custom units.

• The new Simplicity Community: Blockstream announced the official launch of the Simplicity Community, a place for devs to discuss the latest technical developments on the smart contract language and showcase the latest applications built on it.

• Responsible disclosure of an LND bug: Recently, Bastien Teinturier responsibly disclosed a vulnerability he found on LND nodes running versions before v20.0. Specifically, an LND node would forget about a collaboratively closed channel after one single confirmation, losing protection against chain reorgs. In case of a reorg, an attacker would be able to publish a revoked commitment transaction for the channel. Since the node had already forgotten the channel, it would not publish a penalty transaction, letting the attacker drain all of the channel’s funds.

---

Looking for an opportunity to join up with some bitcoin devs in person? Join us in Berlin this October 1- 3 to talk about payments in Bitcoin!