According to the two companies, the collaboration introduces a self-custodial Lightning Network solution aimed at transforming the user experience.
Spark, the Layer 2 launched by Lightspark, has officially announced a partnership with Wallet of Satoshi, one of the most widely used Lightning Network wallets in the world. This collaboration aims to offer users a “truly self-custodial Lightning experience,” through a beta version.
Representatives of Wallet of Satoshi stated:
“From the start, Spark felt like the missing piece. It gave us the foundation to explore self-custody seriously – abstracting away the complex parts of self-custody so we could stay focused on user experience.”
This development comes at a significant moment for Wallet of Satoshi, which in November 2024 removed its application from the Apple and Google stores in the United States. This decision limited American users’ access to the wallet. However, changes in the U.S. regulatory landscape under the Trump administration have created new opportunities. For Wallet of Satoshi, the partnership with Spark now represents the key to re-entering the American market.
According to Spark, the new Layer 2 solution removes the need to manually open LN channels, worry about routing, pre-fund liquidity, or directly manage nodes.
The announcement of this partnership fits into a broader context. On May 22, the company had already announced a partnership with Breez to launch a new implementation of the Breez SDK, built on Spark’s native Layer 2 infrastructure.
Community reactions
Not all Bitcoin community members welcomed the news enthusiastically. Many pointed out that the main issue lies in Spark’s trust model.
Through a post on X, developer Matt Corallo criticized the use of the term “self-custody” associated with Spark, stating:
In response, Kevin Hurley, CTO of Spark, clarified the platform’s trust model. Hurley explained that Spark relies on one or more operators who must behave honestly only at the point of transfer, deleting the key once the operation is complete. If this happens, no one can access the funds in the future, even in the case of hacks or malicious behavior. He also emphasized that users remain free to exit the system at any time, without operators being able to block or censor them.
Corallo replied, acknowledging that Spark’s model is a step forward compared to traditional custodial services — where keys can be seized or stolen — but clarifying that it is still a trust-based system relying on operators. This condition, he said, is far from the concept of self-custody, where control of funds lies solely with the user, with no counterparty risk. Corallo also warned that if an operator were compromised, it could still steal recent funds without users realizing it immediately.
Pierre Corbin, co-founder of Flash, explained:
John Carvalho, CEO of Synonym, commented:
