POA and xDAI take center stage at ETHDenver 2019


POA and xDAI take center stage at ETHDenver 2019

We are still recovering from ETHDenver 2019! We saw many old friends, made connections with new and exciting projects in the space, and met hackers from all over the world who deployed their projects to the POA network and the xDai chain.

The xDai chain, which is a POA based sidechain, was everywhere - the local currency buffiDai was deployed on this chain. All food truck vendors accepted buffiDai, and participants were blown away by the speed and low cost of the network as they bought food and drinks or sent xDAI to one another.

The burner wallet UI, developed by Austin Griffith, made the xDAI chain irresistible to use, and collaborations with many others including MakerDAO, Wyre, Gitcoin, Solidcoin, Qauntstamp, & Status helped bring a local crypto economy to everyone in attendance.

POA was a major sponsor of the event, and it gave us a lot of exposure to the community and opportunity to spread the word about the POA Network. We even sponsored the local beer, Bufficorn Ale!


We presented on POA and xDAI over several days, including a mainstage Friday talk by Igor Barinov titled “Creating xDai: Using the Open Source Tools From POA”. Igor explained the benefits of many POA tools such as BlockScout to view transactions, TokenBridge for achieving horizontal scalability, and on-chain governance tools that impact vertical scalability.

At the end of his talk, Igor posted QR codes on the big screen containing xDAI and audience members quickly tried to be the first to claim the coins. By the time the price reached $10, everyone was scrambling to be the first to scan!

This talk demonstrated how easy it is to use xDAI, and set the stage for the keynote later in the evening. POA’s technical writer Andrew Gross reiterated the benefits of using a POA based sidechain, mainly the blazing speed and super low fees! By adding stability, which is introduced by pegging xDAI to DAI, a real-world, real-time commerce system is created.

On Saturday, Igor participated in a panel called “#Buidling the Infrastructure for Adoption” with members of Clearmatics, Mainframe, and The Graph. The participants discussed developer tools, data availability, and cross-chain bridges that can make the Ethereum ecosystem more accessible to developers and users.

Throughout the weekend, Victor Baranov and Sky Minert fielded questions at the POA booth, explaining the benefits of POA to visitors and answering questions from hackers so they could deploy to our networks.

By Sunday, many teams had chosen to use POA network technology for their hackathon projects. After a rapid judging process, we chose the top 10.

Hackathon Projects

The projects this year were fantastic! Many set out to improve the burner wallet/xDAI experience, and several had a social focus - like creating an education token or helping local food producers. It wasn’t easy to narrow our bounty for the top 10; every project was well done and required a lot of effort and hard work from the teams.

Here is a brief synopsis of our winners. We’ll provide more details about the projects in a follow-up post.

  1. SPITL: A smart contract allows users to send a tip (in xDai) which is automatically split amongst multiple recipients. One potential use case is coffee shops, where a portion of the tip can go to the coffee grower themselves. Merchants set the split percentages, and a patron simply scans a QR code and enters the total amount of the tip. SPITL deployed their app on the xDAI chain to take advantage of the efficiency, speed, and low fees.

  2. Ethergram: This telegram client enables users to send and swap cryptocurrency securely using only the telegram @nickname. The application supported xDai and buffiDai as well as ETH, DAI and other ERC20 tokens. Users can exchange local tokens, such as buffiDai, over telegram with no downloads required.

  3. DAINO: A chrome extension adds a button to a user’s social feed, allowing for easy gifting of xDai to anyone. This project created an excellent UI and made tipping or sending small amounts of xDAI a seamless (cheap and near-instant) experience on twitter and other social platforms.

  4. zDAI: This project uses zkSnarks to allow for confidential transactions in the burner wallet. When using zDAI, transactions are confidential and private, eliminating a traceable history of transactions. The zDAI project won several awards at ETHDenver for its useful privacy enhancements to the burner wallet experience.

  5. NABU: A token system that introduces cryptocurrency to the higher education system. Students can earn NABU (the NABU token) based on their performance in their classes on a weekly basis. Tokens can be used to pay for school expenses, like tuition, books, supplies and more. This project was deployed on the POA network to take advantage of the low transaction costs.

  6. muggleDai: A simple burner.js allows merchants to add an xDai payment option for their websites. This included wallet UI tweaks, a Wyre ramp, and a liquidity relayer for speed. Providing web 2.0 merchants with easy-to-add crypto functionality to their current payment gateways provides an opportunity for more crypto adoption.

  7. Spin.fm: This application allowed users to create private dance rooms where music is shared in real time amongst the participants. ERC721 tokens deployed on the POA Network allow users to create their own unique avatars.

  8. Splunk: This data search and visualization tool was quite prominent at ETHDenver, winning the ETHDenver WOW award and providing real-time analytics at the MakerDAO after party. Docker containers provide an easy way to spin up a POA instance, and analytics are available across multiple chains simultaneously.

  9. React-burner-wallet: The team created an npm package for the xDAI burner wallet. This project aims to allow developers to easily integrate the burner wallet (and xDAI payments) into any web application, potentially increasing adoption.

  10. Merchant: A point of sales system that enables small business to accept xDai, buffiDai, and any other currency. Users simply create a menu of sellable goods and Merchant automatically generates QR codes for complex orders.

Word cloud visualization from Splunk shows on-chain messages customers added to food orders

In addition to the winners, there were several other projects that deployed on POA or xDAI. We were excited to provide this platform for hackers, and glad that many took the opportunity to use our networks and make contributions toward improving the ecosystem.

We will follow up soon with the teams to see how these projects evolve and learn more about their experiences using POA Network’s many tools.

Final Thoughts

ETHDenver 2019 lived up to the hype this year, and it was amazing to be involved with so many aspects of the hackathon. At the maker space, way up on the 6th floor, a group gathered BlockScout data to visualize food truck activity throughout the day. There was so much real-time data available, and this allowed for some interesting number crunching. Did location matter for how many sales each food truck made? Which truck had the most repeat visitors? Which address used the most buffiDai? These and other questions were answered thanks to the easy integration with BlockScout’s API.

The Greek food truck was the winner - and it was the closest to the door! We’re not sure what conclusions to draw from this, but we certainly enjoyed our gyros! We are interested to see how the local token economy and crypto experience created in Denver carries over to the next hackathon, and to other community events, as adoption of xDAI and other POA sidechains continues to move to the mainstream.