Blockchain security solutions, games and storytelling dominated the winning projects at the ETHDenver 2024 BUIDLathon, the largest and oldest hackathon for Ethereum developers, which ended on Sunday evening.

At the close of the 9-day hackathon, BUIDLathon judges selected five winners from over 200 competing projects at the seventh annual hackathon that distributed about $1,000,000 in sponsor bounties and prizes.

HoneyPause, an onchain security project; Egg Wars, a chicken-and-egg NFT game; Odin, a dapp security feature; BeFit, a competitive fitness social media game; and Sekai, an AI-interactive story-building platform, were crowned the winners and awarded $1,000 in prize money in addition to incremental prizes and awards throughout the competition. There were five tracks the projects competed in: Infrastructure + Scalability, Identity + Privacy + Security, DeFi + NFTs + Gaming, DAOs + Communities, and Impact + Public Goods. Each track had three finalists who earned $5,000 in cash plus additional prizes such as free tickets to next year’s ETHDenver valued at up to $12,500. 

ETHDenver 2024, as an organizer of the BUIDLathon, put forward $142,500 as rewards for the top projects in each track, and the remaining prize pool came from the 50 additional partners that sponsored the hackathon, including Arbitrum, Solana, Wormhole, RISC Zero, Base, Linea, Chainlink, Hedera, Polkadot, Near and Lukso.

The Winning Projects

The winners were selected by five hackathon judges, who themselves were chosen by developers and other experts in the Ethereum ecosystem from 2,900 applications. Judges were nominated based on how much they embodied the ethos of ETHDenver, “#BUIDL,” which is a concept combining the elements of education and community. The judges, Nader Dabit, Casey Gardiner, Austin Griffith, Solange Gueiros and Min Kim, each selected a winner. 

Dabit is Eigen Labs’s director of developer relations and has a GitHub page that dates back to 2012. Gardiner is a board member of Spork DAO as well as the lead protocol engineer at Harmony. Griffith works for the Ethereum Foundation and focuses on developer onboarding and tooling. Gueiros is a blockchain developer advocate at Chainlink Labs. Kim is the co-founder of design firm Airfoil.

Dabit’s Favorite: HoneyPause

Dabit’s favorite was HoneyPause, a project in the Identity + Privacy + Security track. The problem the HoneyPause team wanted to address was how onchain projects operate at a “major security disadvantage” due primarily to the continuing evolution of sophisticated threat actors. Indeed, the number of funds stolen from crypto platforms in 2023 amounted to $1.7 billion, according to a Chainanalysis report published in January. 

HoneyPause team members Justin Schuldt, Lawrence Forman and Jordan Cason settled on a solution to empower white hats.

Hackers who scan software code to identify potential vulnerabilities are identified by their metaphorical black and white hats. Black hats, like notorious North Korean hacker group Lazarus, intentionally capitalize on identified weaknesses of a protocol’s code base, actively exploiting vulnerabilities to loot crypto projects and sometimes sell their discoveries to underground marketplaces. 

White hats historically notify protocol developers upon discovering a bug that requires patching. Some have been known to exploit the bug to acquire funds before a malicious actor can, but then return the funds back to the rightful owners. In return for disclosing bugs and returning funds, projects typically reward white hats with a bounty of some kind, but not always. 

“We actually need more white hats and we need to empower and incentivize them to trustlessly pause your protocol if they can prove that you have a critical exploit, and that’s where HoneyPause comes in, said Forman, who is a blockchain security engineer at venture fund Dragonfly Capital, during the team’s presentation.

HoneyPause is an onchain exploit bounty tied to a circuit breaker. White hats, if they prove a smart contract exploit, can use HoneyPause to pause the affected protocol and collect a bounty for it.

Griffith’s Pick: Egg Wars

Griffith picked Egg Wars as his favorite project for the BUIDLathon. Egg Wars is “a game where players compete to build the biggest army of chickens and produce the most $EGG,” the project stated on its DevFolio page. It competed in the DeFi + NFTs + Gaming track. 

The game, meant to be both simple and fun, was inspired by three chickens named Coco, Froyo, and Thunder, who belong to one of the team members. 

Egg Wars is an onchain game consisting of two different assets, chicken NFTs and egg tokens. Players can use eggs to feed their chickens to increase the chicken’s egg production “or you can use the egg to throw at an enemy chicken and decrease its level or you can also try your chances to hatch an egg where you have a 20% chance of birthing a whole new chicken,” said one of the team members of Egg Wars on stage.

Egg Wars is currently deployed on the Sepholia test network of layer 2 blockchain Base, which was incubated by crypto exchange Coinbase. Steve Klenbanoff, a full stack engineer at PartyDAO; Jeremy Lack, full stack engineer in Web3; John Palmer, a founder of PartyDAO, and Regular pOpps, who self-described as the founder of Regulars, were the four team members.

“This is a wonderful hackathon project,” said Griffith, the judge, after the presentation. “This is exactly what hackers out there should strive for. There’s some really brilliant mechanism design happening here, with a really silly element attached to it.”

Gardiner’s Winner: ODIN

Gardiner chose as his favorite ODIN, which helps decentralized applications pause their smart contracts before “malicious transactions that break protocol invariants (usually hacks) are executed,” according to the project’s DevFolio page. Like HoneyPause, ODIN competed in the Identity + Privacy + Security track.

Invariants are properties of a protocol’s system that should always hold true, and if it doesn’t hold true for every block, the protocol has a substantial problem. One example of an invariant, provided by the team, is how the sum of all lending transactions minus the sum of all borrowing transactions from a smart contract should equal the tokens left in the contract.

ODIN not only enables a marketplace where decentralized applications pay block builders for pausing smart contracts but also has block builders bonded on EigenLayer so they don’t maliciously pause. “It’s like a crypto economic safe using the EigenLayer system to throw a circuit breaker in the block builder, to get out ahead of everyone,” said Griffith after the team finished presenting.

Anup Swamy Veena, a senior blockchain security engineer at Coinbase, and Anto J., a fullstack Web3 developer, were the two members of ODIN. 

Gueiros’ Selection: BeFit

BeFit, created by University of Waterloo students William Wang and Xavier DMello, was  Gueiros’ top selection. The project is an iteration of photo-sharing platform BeReal, which allows users to post one photo a day to show their friends what they are currently doing. Users can only see their friends’ BeReal photo if they post to the platform. 

BeFit is “BeReal but with pushups,” as outlined by the project’s DevFolio page. The application rewards users with NFTs for regularly doing pushups, acting as a proof-of-history for the user that incorporates a “collectible and competitive element to exercise.” 

The project is under the Impact + Public Goods Track and was rolled out on the Sepholia test network of layer 2 blockchain Arbitrum, according to Wang and DMello’s speech during their presentation. Wang did 10 pushups with DMello recording on a phone for the live demonstration of their project.

“I choose BeFit, because I am an active person,” said Gueiros in an interview with Unchained. Gueiros, who is also samba teacher, said she liked how the team incorporated exercise and a social element into its design. 

When Unchained asked the team members what the key factor was for winning hackathons, Wang said, “Just make something fun, make something ideally useful, but honestly mostly fun, something entertaining that’s not boring.” 

DMello, who is the chief technology officer of the Waterloo Blockchain Club, also told Unchained that venture capital firms have approached the two students for their BeFit project. “We had like four walk up to us,” said DMello. “One of them that invested in StepN, they want to invest in us… they said they didn’t see the social aspect in these kinds of fitness apps before and really liked it,” added Wang.

StepN is a Solana-based project where players can earn tokens through walking, jogging, and running. The project was popular, especially during the COVID-19 time period. 

While Wang and DMello have participated in other hackathons like ETHGlobal NYC, ETHDenver’s 2024 BUIDLathon was the largest for them. 

Min’s Choice: Sekai

Min selected Sekai, an AI-driven interactive story building platform. John Wi, Kaiser Kim and Tommy Rodriguez focused on the problem of how “the current media journey currently incentivizes passive consumption over emotional resonance … leaning to user relationships dominated by spectatorship over collaboration,” said Kaiser Kim, one of the three members of the team.

Using Sekai, storytellers can make plotlines by generating text, images and audio through AI tools while viewers can engage and influence the story direction by contributing ideas and co-creating content. According to Kim, Sekai leverages the following technologies for their platform: Story Protocol for IP licensing, a Friend.tech inspired social-fi modal, AI-generated content and composable Web3 blocks like NFTs.

Min said she was specifically looking at the design considerations of the various projects. “So obviously, the kind of product I picked had the most polished user experience and [user interface],” Min said to Unchained in an interview. Every team had a great idea, “all have a great technology behind [them], but it’s a matter of how you communicate your technology to human beings …. There’s a huge opportunity for design to play a role there, so that was my consideration.” 

A Noticeable Lack of Diversity

While ETHDenver’s BUIDLathon is an event where developers have the chance to advance the blockchain ecosystem,” all individuals in the 15 groups that presented on stage during this year’s hackathon appeared to be male, presenting a noticeable lack of gender diversity. Two of the five judges on the panel, however, were female.

Even though Unchained did not confirm the gender or sex of each person who presented on stage, one of the judges also made the same observation. “Definitely, that was something I also noticed,” said Min.

“We definitely need more diversity, not just gender, but people with different backgrounds. I think the Web3 and hacker community in general has some level of diversity in that people with traditional linear career paths are different, but as a community, it’s important to have the awareness,” Min added.

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