0xHack 2021: Chainlink Bounty Winners

We’re excited to announce the Chainlink bounty winners from the 0xHack 2021 Hackathon. These winning projects presented new advanced smart contract applications that leveraged a variety of Chainlink oracle network solutions, such as Chainlink Price Feeds for fetching tamper-proof market data, Chainlink VRF for provably fair blockchain gaming, and External Adapters for delivering FitBit data on-chain to trigger tokenized fitness rewards. These builds demonstrate the wide range of off-chain services that developers can access through the Chainlink Network for creating new types of hybrid smart contract applications.

Bounty winners were awarded a total of $5,000 in prizes, with $1,000 going to each of the five top projects. Each winning 0xHack project used Chainlink oracles to connect smart contracts to off-chain data and resources. These hackathon prizes are intended to support and motivate builders across the DeFi and smart contract ecosystem who are exploring the many oracle functionalities provided by the Chainlink Network.

Thank you to all the participants, sponsors, and judges at the 0xHack event for coming together to #BuildwithChainlink and push hybrid smart contract innovation forward.

The winners below are highlighted in alphabetical order.

For the Chainlink Jockey project, developer Sagar Beharasagar133 built a horse racing gaming dApp that uses Chainlink VRF to provide random running speeds for in-game racehorses. Each horse in the game is an NFT, and within a certain time period users can stake funds on an NFT horse. Chainlink VRF supplies verifiably random numbers to create a speed of each horse, which determines a winner in a tamper-proof and unpredictable way. Chainlink Jockey then automatically pays out the prize to the stakers who selected the winning horse.


Link Fit built a platform to incentivize exercise by rewarding users with tokens. Developer Xand Ronus built the platform on Ethereum and used Chainlink’s Any-API External Adapter framework to integrate with FitBit devices and track daily steps. Chainlink External Adapters are used to deliver the FitBit API data on-chain to trigger rewards in the dApp. This is a creative method for bringing IoT data on-chain by using Chainlink as flexible blockchain middleware.

Developers Luis Callero and Juan Meregone built Mega_Link as a graphical drag-and-drop crypto converter running on Polygon that allows users to take an asset and drop it into a location on screen to engage an asset swap. Mega_Link uses Chainlink Price Feeds to determine the correct exchange rate for the two assets. This is an interesting take on a game-like user interface to provide additional options for in-app user experience while relying on secure, high-quality market data powered by Chainlink.

NFT Booster Pack

Developer Edwin Guajardo deployed the NFT Booster Pack dApp on Polygon to create and buy NFT packs with customizable rare items inside each pack. The dApp uses Chainlink VRF to determine the contents of the pack in a provably random way. This use case demonstrates how Chainlink’s native integration with layer-2 networks like Polygon empowers  developers to build cost-efficient gaming dApps that have seamless access to a verifiably secure RNG for enabling dynamic player experiences.

Proof of Workout

Developer Tippi Fifestarr created an exercise incentive program that rewards users with “NFBody” NFTs that have verifiably random traits. Proof of Workout users upload a video of themselves exercising, and a community of participants then verifies that their exercise activity is legitimate. Upon community validation, submitters are rewarded with NFTs. The NFTs are assigned random traits using Chainlink VRF, ensuring attributes are randomly selected in a tamper-proof manner. The Proof of Workout project is still under construction and is adding several more features to further incentivize community engagement around exercise with dynamic NFTs.

Congratulations again to the winners, and thank you to all the teams and developers who used Chainlink in the 0xHack hackathon. We are always excited to support experimentation and innovation across the smart contract ecosystem by encouraging projects that are exploring the vast array of use cases enabled by Chainlink decentralized oracle networks.

Chainlink is sponsoring the upcoming HackMoney 2021 from ETHGlobal. Register today to compete for a shared prize pool split among all participants who successfully use Chainlink to make a state change on any blockchain. We’re looking forward to seeing more standout projects like the 0xHack Winners at HackMoney and at future hackathons supported by Chainlink.

Also, if you’re new to smart contract development and want to level up for upcoming hackathons, be sure to register for the Chainlink Summer 2021 Smart Contract Developer Bootcamp. We’ll cover the fundamentals of smart contracts, Solidity, popular development environments, and how to build with Chainlink oracles. Registration is now open so secure your spot today.

If you’re a developer and you need resources to get your application connected to Chainlink Price FeedsChainlink VRF, Chainlink Automation, or to access any API, visit the developer documentation and join the technical discussion in Discord. If you want to schedule a call to discuss the integration more in-depth, reach out here.

Website |  Twitter | Reddit | YouTube | Telegram | Events | GitHub | DeFi

Need Integration Support?
Talk to an expert
Get testnet tokens
Read the Docs
Technical documentation