DEFAULT

This workshop will take you through a run down of zkSync's Paymaster and will allow pay your transactions with USDC (or any token) using API3's dApi price feeds while also allowing the options of allowing free transactions to any holder of a specified VIP NFT.

API3

Developer Relations

Billyjitsu

Use API3's dApi price feed in zkSync's paymaster

Opening

Team Formation

Hot and Fresh dinner served for your bellies!

Dinner Day#1

In this two part workshop, attendees will learn about how Scroll is scaling Ethereum with its zkEVM. First, you’ll see how easy it is to deploy your contracts to Scroll using a handful of popular developer tools. In the second half of the workshop, attendees will learn how to use Scroll to verify zero-knowledge proofs built in Noir, building a zk voting app. Part 1 will be in English, with Part 2 done in Spanish.

Scroll

Raza Zaidi

Ahmed Castro

Building on Scroll – from beginning to AppliedZK (English & Spanish)

Sharing experiences and best practices on setting up, scaling and running nodes / validators, including monitoring and alerting based on open source products

Gnosis

Cloud Engineer

Anton D.

Running Gnosis nodes and validators

Join Anthony DiPrinzio and Nse Barna from Aleo as they provide an introductory lesson on zero-knowledge (ZK) technology and how it can be applied to real-world use cases. They will also include a high-level overview of Aleo's architecture, domain-specific programming language ([Leo](https://leo-lang.org/)) and a deep dive into how ZK technology will form the building blocks for the next wave of decentralized applications. If you’re a developer interested in building private, programmable applications this is the workshop for you!

Aleo

Head of Ecosystem Growth

Anthony DiPrinzio

Chief of Staff

Nse Barna

Demystifying ZK Programming: Decentralized Private Computations on Aleo

In the era of digital assets and blockchain technology, we present an immersive, hands-on workshop that aims to deepen your understanding and skills in the exciting world of Non-Fungible Tokens (NFTs) and staking mechanisms.

The workshop is tailored to cater to artists, investors, developers, and enthusiasts alike who are interested in delving into the transformative potential of NFTs and how they interact with the dynamic mechanism of token staking.

Participants will explore the conceptual and technical aspects of creating unique NFTs with various levels and rarities. Through this journey, you'll understand the profound layers of blockchain technology and how it is revolutionizing the digital landscape.

In addition, we'll unravel the process of creating a specific token for staking purposes, enabling attendees to understand how to stake these tokens within their uniquely created NFTs. This not only adds value and utility to your digital assets but also provides an opportunity to gain insights into the economic models within the blockchain ecosystem.

**Key Workshop Takeaways:**
- Comprehensive understanding of NFTs and their intrinsic properties.
- Hands-on experience in creating unique, multi-level NFTs with various rarities.
- Insight into the concept and process of token staking within NFTs.
- Step-by-step guidance on creating a staking token specific to your NFTs.

Create your piggy-bank NFT! by XDC Network

Take a break from building to grab some lunch!

Lunch Day#2

Endaoment invites developers & builders for good to a workshop exploring use cases & applications for new web3 tooling that makes crypto giving flow. Learn how to find contract addresses for global organizations, format donation transactions and deploy new contracts for nonprofits. If you're passionate about bridging web3 and impact, join the Endaoment.Tech team to learn about our new developer tools and innovate together live, as a community. #consciouscrypto

Endaoment

President & CEO

Robbie Heeger

Onchain Programmatic Giving with Endaoment’s SDK

Learn the core pieces of the Union credit protocol, How smart contract based credit underwriting and borrowing work. And a practical example of  How to build a contract that autonomously underwrites any address that holds a specific NFT.

Union Finance

Founder

Jacob Shiach

How to build on Union

The introduction of Account Abstraction to the zkSync Era scaling solution realizes the concept of smart contract accounts (SCAs) for functionality such as social recovery, spending rules and flexible validation. 

Paymasters enable gas in ERC20 to be paid from a separate contract, basically enabling gasless transactions. At the moment, the majority of EVM-based Externally Owned Accounts (EOAs) have a self-custody model, meaning they cannot utilize a paymasters contract. However, on zkSync Era paymasters can be utilized by both EOAs and SCAs. 

Use zkSync’s paymaster with dAPIs to power existing dApps on zkSync Era

dAPIs can be used within zkSync’s Paymaster contract to enable users to pay for gas in any token of their choice on your platform. Within a paymaster, dAPIs can provide price data on-chain for execution.

Participants are required to implement a custom API3 zkSync’s paymaster within their projects that can sponsor the gas fee for users’ transactions on their dApps/platforms.

Participants can follow the [Paymasters with dAPIs on zkSync](https://github.com/vanshwassan/zk-paymaster-dapi-poc) guide to implement your ideas around the same.

Resources: 

- [Using dAPIs on zkSync Era Testnet](https://vanshwassan.medium.com/using-dapis-on-zksync-era-testnet-30f12efdd95f)
- [Hello World on zkSync Era Testnet](https://era.zksync.io/docs/dev/building-on-zksync/hello-world.html)
- [zkSync Paymasters Integration](https://era.zksync.io/docs/dev/tutorials/api3-usd-paymaster-tutorial.html)

📣 Utilizing API3 data feeds within zkSync Era's Paymasters

Dinner served hot and fresh before your late-night codesprint!

Dinner Day#2

Get your energy levels up for the final codesprint!

Breakfast Day#3

Yellow is proud to sponsor ETHBarcelona's Demo Day Breakfast! 

Join us for a morning of innovation and blockchain awesomeness as we warm up to pitch 🥐💡

Yellow, a team led by some blockchain pioneers, focuses on state-channel infrastructure, DeFi, and liquidity, revolutionizing the next-gen DeFi experience and supporting developers and entrepreneurs. 

If you want to learn more about how Yellow is decentralizing trading for real: www.yellow.org TG: @yellow_org. 

Connect with Yellow at ETHBarcelona's Special Demo Day Breakfast!  💛

Breakfast Day#3 with Yellow

Lunch is here for your post-judging hunger :)

Lunch Day#3

Results are here! Join us for the closing ceremony of ETHBarcelona

Closing Ceremony

Turing Capital

Jorge Schnura

Invicta Blockchain Capital

Gonzalo Ferradás

Safe

DevRel

Germán Martínez

Fullstack Dev Consultant

Valerio Coltre

Developer Advocate

Insha

YARD Hub

Yaroslav Shakula

Asymettry Finance

CoFounder

HannahJoJo

Judge

Olga Grinina

KlimaDAO

Core Contributor

Marcus Aurelius

Ledger

Nicolas Consigny

Kawach

Lead Security Researcher

Pranav Garg

Marketing & DAO Ops Āut Labs / Co-Founder ART3

Libby Porteous

Blockdaemon

Lead of Developer & Protocol Relations

Robbie Kruszynski

Authentick Technologies

Web3 Strategist

ProtoFire.io

Blockchain Buidler and Entrepeneur

Cristian Malfesi

Scientific Researcher at CSIC | JSR at SpearbitDAO

Luksgrin

Intrinsic Global

Marc Griffiths

Cryptonikas

Software Engineer

Giselle Chacon

Toucan Protocol

Lena Hierzi

Bueno

Artists Relations

Tomas Mujica

Panther Protocol

Co-Founder

Anish Mohammed

Request

Community Manager

Alex Stoicescu

TPM Core Devs

Philippe Schommers

GnosisChain

Stefan George

R&D Engineer

Filip Pajic

Swagtimus.eth

zkSync

Head of Developer Advocacy

albicodes

Head of Growth

XDC Foundation

Arturo Cantera

Ecosystem

Ben C

Communications & Community

Dae Moyer

Devfolio

Denver Dsouza

Developer

Mark Akinwale

Team Cryptonikas

Joanna

Natalia Suarez

Giveth

Griff Green

OSO AI

Team OSO AI

Fred von Graf

Preet Parekh

CSIC

luksgrin

IT Rock

CEO & Founder

Sebastian Colombo

Cartesi

Daniel Ortega

Mirai dao

Founder & CEO

Amalia Grochal

XR Designer

Sonya Seddarasan

ETHBarcelona

In this track, participants are challenged to explore the fusion of culture, art, and technology. Teams will develop innovative projects that leverage technology to enhance artistic expression, celebrate cultural diversity, or create immersive digital experiences. 

Culture & Art

The Web3 Social track invites teams to build projects that leverage decentralized technologies to revolutionize social interactions. Participants will develop social media platforms, community-driven initiatives, or collaborative tools that empower individuals and enable new forms of peer-to-peer engagement. From decentralized social networks to decentralized identity solutions, teams have the chance to shape the future of social connectivity in the Web3 era.

Web3 Social

Teams in this track will focus on building tools to facilitate decentralized decision-making and community participation. Whether it's a DAO for funding public goods or a DAO for decentralized project management, teams will explore the possibilities of collective ownership and decision-making.

DAOs

In the DeFi & Dapps track, teams will dive into the world of decentralized finance and applications. Participants will build projects that enhance financial inclusion, create new decentralized financial instruments, or develop innovative decentralized applications (Dapps) for various use cases.

DeFi & Dapps

Teams in this track will embark on an exciting journey to create projects that push the boundaries of the metaverse and gaming. Participants will develop immersive virtual reality experiences, blockchain-powered gaming economies, or innovative multiplayer games that leverage the potential of decentralized technologies. From building virtual worlds to exploring the potential of non-fungible tokens (NFTs) in gaming, teams will shape the future of interactive entertainment.

Metaverse & Gaming

In this track, teams will focus on projects that make a positive impact on society. Participants will develop solutions that address social challenges, promote sustainability, or enhance educational opportunities. Whether it's a platform for crowdfunding public goods, a blockchain-based solution for tracking carbon footprints, or an educational tool that utilizes decentralized technologies, teams will work towards creating meaningful change.



Public Goods, Impact, Education

Teams in the Infrastructure & Scalability track will tackle the technical aspects of the Web3 ecosystem. Participants will build projects that improve blockchain scalability, enhance interoperability between different networks, or develop novel infrastructure solutions. 

Infrastructure & Scalability

In the Privacy ZK track, teams will focus on privacy and zero-knowledge technologies. Participants will develop projects that preserve user confidentiality, enhance data privacy, or implement zero-knowledge proofs in various applications. Whether it's building a privacy-focused messaging platform, developing privacy-preserving smart contracts, or creating tools for secure data sharing, teams will explore the importance of privacy in the decentralized world and develop innovative solutions to protect user information.

Privacy ZK

Select this track to be eligible for the prizes offered by zkSync

zkSync ∎

Select this track to be eligible for the prizes offered by Request Network

Request Network

Select this track to be eligible for the bounties by Gnosis Chain

Gnosis Chain

Gnosis chain

Select this track if you're building on AI x Gnosis Chain

Gnosis Chain - AI Track

Select this track if you're building Data Oracles and Price feeds for XDC Network

XDC Network: Data Oracles and Price feeds

Select this track if you're building Collateralized Debt Position (CDP) with XDC as collateral

XDC Network: Collateralized Debt Position (CDP) with XDC as collateral

Select this track if you're building your project around XDC staking

XDC Network: XDC staking

Select this track if you're building around Decentralized Finance (DeFi) on XDC Network

XDC Network: Decentralized Finance (DeFi)

Select this track if you're building Decentralized Exchanges (DEX) on XDC Network

XDC Network: Decentralized Exchanges (DEX)

Select this track if you're building around NFT Rarity sniffers on XDC Network

XDC Network: NFT Rarity sniffers

Select this track if you're building on Social Media crypto bots (alerts) for XDC/XRC-20/XRC-721

XDC Network: Social Media crypto bots (alerts) for XDC/XRC-20/XRC-721

Select this track if you're project is using AI to pull community data (projects, DAO, etc) and make it available in a data store.

Staying up to date on all the projects you are invested or involved in is impossible with information fragmented across discord, telegram, twitter, forums, snapshot, and so on. 
OSO wants to make this easier by aggregating all of this information and being able to allow our users to query in natural language asking for specific updates and information right from their messenger (currently supports telegram). OSO also lets you select projects you want to receive updates on and delivers a daily digest of information from the projects you select.
We are looking for the team / individual that can best pull this information from multiple sources, into a central store (Pinecone, Deeplake, SQL, other), where OSO can integrate this information and make it available to those users that hold interest in the project.  This can be done using ReactJS preferred (or other web framework) where OSO can query the pages  for data and use the resulting data.  The more reliable the data and the easier it is for OSO to use the data the more points will be awarded.

Bonuses:

- For cleaned data, make the data consistent and machine readable
- Data that has sentiment analysis included
- Data that has been ingested into a vector store for easy use from our language models

Possible Ideas:

- Sentiment analysis of twitter/discord for a specific project
- Intake process to make it streamlined for any project/community to add their data sources to OSO. ie React page that allows projects to add their RSS or other feeds.
- Integrating specific communities/projects/tokens and channels from multiple sources which can then be queried by the end user in OSO or pushed in a daily update.

How to Start:

OSO utilizes a custom AI agent framework that preprocesses queries to determine task vs informational items. The framework is written in python and runs in an AWS serverless environment.  OSO uses ReactJS pages to interface with outside API's, present information to our users in a mobile web friendly format, etc.  As an example, pages have been included for reference which shows our DAO governance processing.

- Identify a matrix of sources for projects
- Identify methods of querying the sources
- Identify a storage method for the data
- Process the data (clean, sort, sentiment, etc)
- Respond to query with data and details

Oso Track: Use AI to pull community data

OSO.AI

Select this track if your project is based around AI-created NFT minting

### Use AI generated art to mint NFT using OSO

AI generated art is getting to be amazing in design, style and quality. We are looking to use AI generated art to create custom NFT's and mint them within OSO.  By utilizing the messenger interface of OSO our users should be able to create a custom image, and mint it all from within our messaging app (currently using telegram).

We are looking for the team / individual that can integrate image creation through API calls, and taking the finished image and minting it all from within the OSO app.  This can be done using ReactJS preferred (or other web framework) where the OSO user can activate the NFT generation as a call to the React pages.

**How to Start:**

OSO utilizes a custom AI agent framework that preprocesses queries to determine task vs informational items. The framework is written in python and runs in an AWS serverless environment.  OSO uses ReactJS pages to interface with outside API's, present information to our users in a mobile web friendly format, etc.  As an example, pages have been included for reference which shows our DAO governance processing.

- Identify AI image generation API to use:
    - Skybox by Blockade Labs
    - Midjourney
    - DALL·E 2
    - StableDiffusion
    - Bing
    - Others
- Take a prompt from the OSO user
- Filter the prompt from the user to assure it doesn't violate human decency
- Generate the image and present it to the user
- User approves, edits or restarts
- Once approved give the user the option to mint to NFT on wallet of their choice
- Return image link and chain summary showing success

OSO Track: AI-created NFT Minting

Select this track to be eligible for bounties by Aleo

zkGaming on Aleo

Select this track to be eligible for prizes by Aleo under this track

ZeFi on Aleo

Select this track if you're building for this Endaoment bounty

Endaoment - Application of enabling yield splits to nonprofits

Select this track if you're building for this particular Endaoment bounty

Endaoment - Tool for viral donation campaigns

ETHBarcelona

ETHBarcelona

$109,350

Available in Prizes

$109,350

Available in Prizes

Speakers & Judges

Speakers & Judges

Sponsors

Sponsors

Sponsors

Sponsors

FAQs

FAQs

Hacker reviews

Hacker feedback

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