Bitcoiners Sprint to Improve Lightning Network in 2-Day Virtual Hackathon

Unable to meet in person, developers around the world collaborated by videoconference for a 48-hour stretch to refine Bitcoin’s Lightning Network.

AccessTimeIconJun 2, 2020 at 8:00 a.m. UTC
Updated Sep 14, 2021 at 8:47 a.m. UTC

As coronavirus is changing everyone's lives, making it harder to go outside or interact with friends and family, people are leaning more than ever on digital video platforms to live a "normal" life. That includes Bitcoiners who are fine-tuning the organization of hackathons in the virtual realm.

Several times around the globe, German lightning research startup Fulmo has put on the event Lightning Hack Day, where developers gather to hack and share new exciting ideas to further the network or the lightning-related projects they've been working on. 

With coronavirus making it unwise (and even legally restricted) to travel and gather in large groups in meat space, they've moved online, rebranding the event to the Hack Sprint. "The world is still in lockdown, but that doesn't stop Bitcoiners to gather around the virtual fireplace to keep building and sharing knowledge!" tweeted Fulmo a couple of weeks prior to the two-day event, which took place May 9 and 10.

The event is dedicated specifically to the lightning network, a technology considered critical to Bitcoin's future. It aims to solve huge problems with payments in the leaderless currency, such as significantly scaling how many transactions it can handle and speeding up payments to be instant, as shoppers expect.

The hackathon is an "unconference," since participants do much of the (self-)organization. They can get what they want out of it. Before the Hack Sprint, developers posted "challenges" for fellow hackers to solve, such as a small boost to lightning privacy and building an extension using lightning payments as a method to curb spam on a wiki, where participants can crowdsource information and collaboratively edit content. Some enthusiasts even posted BTC bounties to encourage participation. 

"Anyone is welcome to put up challenges and use the weekend to get some progress. No one is forced to deliver a prototype, but to work and share what their outcomes were," said Christian Rotzoll, DIY node project Raspiblitz creator and organizer of the Hack Sprint.

At the culmination of the 48-hour sprint, developers presented what they built or improved upon, a total of 16 projects, improving the sprawling lightning ecosystem in various ways – either adding new features or using the time to clean up messy code. 

User-friendlier projects

Some projects focused on lightning applications like tipping. That’s a popular early application of the payment system, partly since lightning enables smaller online payments than ever before, with lower processing fees.

Many tipping apps are focused on media, including for Twitter, but developer Michael Bumann finished a proof of concept of such an app over the weekend geared towards donating to developers.

Programming might usually be a high-paying gig, but often developers create software for free to further a technology or cause that they're passionate about. The Bitcoin community, for example, is filled with these people. 

Bumann created a tool to make it easier to automatically tip programmers (specifically the programming language Ruby) who developed open source software a developer used in their own project. 

Teams made a number of improvements to Raspiblitz, a DIY guide for crafting your own lightning node with an interface showing some of the node statistics.

Running your own lightning node is the most trust-minimizing way of using Bitcoin, because you don't have to trust anyone else to tell you what the state of the blockchain is. Without one, a malicious actor could potentially feed a user false information. 

Pseudonymous developer Openoms added a component to Raspiblitz to make it easier to summon the GUI of JoinMarket, one of a few key ways of making "CoinJoin" transactions, which gives users more privacy.

"JoinMarket is the longest standing and most feature-rich CoinJoin software with somewhat less easy to use interface which I am determined to improve. This is a small step taken to make the existing graphical interface easily and safely available for RaspiBlitz users on their desktop," Openoms told CoinDesk. 

Deeper improvements

Other developers focused on making lightning work better under the hood.

Again along the lines of privacy, one developer group created TOR2IP-Tunnelservice, which adds a new feature for lightning users taking advantage of Tor, a privacy tool that hides a user's IP address, which identifies a user's computer and location. 

The tool uses lightning two ways in one. First, it allows a user to tie a public address to the Tor address where their lightning node is running and connected to, without revealing the identity or location of the node.

Second of all, people can pay lightning to use this service.

Lightning developer Rene Pickhardt has been exploring the possibilities of using a different protocol for "routing," which is how a payment moves to one person to another, producing a path that a payment moves through the network to reach its destination. 

Pickhardt proposed a routing protocol just-in-time (JIT) for lightning for the past year, which potentially improves success rate and privacy of the network. For the hackathon, he and a PhD student Michael Ziegler put together a proof of concept, putting the idea into practice for the first time. 

"We finished one minute before 8 p.m." – the time they were supposed to present, Pickhardt said with a laugh. (Especially uncanny since the protocol is called "just in time.")

These are only a few of the projects that were presented at the hackathon. And not to mention, while this hackathon gives this lightning work more exposure, developers are actually working on these types of small improvements every day, attempting to build the future of online money.


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