Core Lightning, the Lightning Network implementation developed by Blockstream, launched its version 26.04 on April 20, called “Negative Routing Fees.”
The update introduces for the first time the ability for node operators subsidize payments that pass through their channels, a feature that could make Bitcoin transactions even cheaper.
What are negative fees?
On the Lightning Network, each payment travels through intermediary nodes that typically charge a small fee for routing that transaction. With negative fees, a operator can reverse that logic and pay a fraction for each transaction that passes through its channel. In practice, this means that some payments could cost the end user less, or even give them a small discount.
The measure is primarily intended for operators to attract traffic to channels with low liquidity or to compete for routing volume. However, it also opens a debate about whether nodes with more resources could use this tool to concentrate network traffic in their favor.
Splicing is now official
Another relevant change in this version is that splicing leaves experimental mode and is enabled by default. This function allows you to adjust the size of a payment channel without having to close it and open it again, which reduces operating costs and eliminates dependence on external liquidity providers. The update also includes two new commands, splicein and spliceoutwhich simplify its use. This type of tools has already been used for some time in wallets such as Eclair and Phoenix, as reported by CriptoNoticias.
On a privacy level, messages between nodes are now padded to a uniform size, making it difficult for third parties to identify activity patterns through traffic analysis. Additionally, the software binaries are approximately 20% smaller, which improves the overall performance of the node and makes it easier to install.
Regarding payments, the version incorporates pathfinding parallelan improvement to the pathfinding algorithm that increases the reliability of transactions. Support for payer notes in xpay and a new plugin for real-time currency conversion are also added.
Version 26.04 is the result of 421 commits carried out in 110 days by 23 contributors, six of them participating in the project for the first time. The team maintains eight bounties open for those who want to join the development.