Last week in bitcoin (Nov 17 - 23)
Highlights from the bitcoin developer ecosystem...
Hi Insiders. This is Tuma, open-source reporter from the Insider Edition. I spent 10+ hours in open-source developer calls in the Bitcoin ecosystem last week. Here is what caught my eye:
Nut November is the month-long hackathon for developers building on Cashu.
During the monthly call, on November 20th, various developers showcased their projects built for Nut November, a month-long hackathon for Cashu builders. With a total prize pool of nearly 1.5 Million sats, this competition will award projects in different categories, such as best overall, most technically challenging, wildest idea, best design, best beginner project and community favorite.
Several projects were presented, all of them including an integration with the Cashu protocol. Some developers built applications, such as a no-kyc casino, called Cashu Casino, a Nostr-powered task board with Cashu bounties, called Taskify, a score-tracking application for playing disk golf with built-in Cashu payments.
Developers’ tool were also built. Bitcoin Skills, for example, provides comprehensive Claude Skills for implementing Bitcoin and Cashu wallet functionalities, QR code generation/scanning and Nostr integration on Shakespeare. Another developer showcased Cyphertap, which provides all Nostr login and Cashu wallet functionalities in a single Svelte component.
PR7905 in Fedimint has been merged, implementing custom and efficient fountain codes for the protocol.
During the weekly call, on Monday 17th, Fedimint developer joschisan announced that PR7905 had been merged. This PR implements custom fountain codes for the protocol, with the goal of efficiently encoding and transmitting ecash via animated QR codes.
Fountain codes are a simple way to send data reliably over unreliable channels. They fit well in applications such as animated QR codes, where the scanner might miss some frames. The original data is split in N simple fragments, which are shown sequentially at first. Then, the system generates an endless stream of ‘mixed fragments’ by XORing randomly selected subsets of those simple ones.
The decoder processes any mixed fragment it receives and XORs away any already-decoded fragments to simplify it. If this reveals a new simple fragment, it is used to unlock others in a chain reaction. This allows for any sufficiently large subset of fragments to decode the entire message, regardless of which specific fragments were received.
PR1160 in BOLTs repository is ready to be merged, including splicing into the Lightning Network specifications.
During the monthly specification call, on Monday 17th, Lightning developers announced that PR1160 was ready to be merged. This PR officially includes splicing in the common Lightning specifications, allowing interoperability between the different implementations.
The ACK to the PR comes after a long series of discussion and interoperability tests made by the developers behind the different implementations. As of today, three implementations are already supporting splicing, Eclair, Core-lightning and LDK.
The PR will be merged soon on top of two other PRs bringing improvement to interactive transactions. These are PR1236, which allows both parties of a channel to initiate RBF, and PR1289, which requires explicit retransmission of
commit_sigin case nodes disconnect in the middle of the signing step.
Looking for an opportunity to join up with some bitcoin devs in person? Join us in Taipei this December 15-17 to talk about standing sovereign with Bitcoin.