Arbitrum Open House NYC: Online Buildathon
Build what’s next
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Host by
Arbitrum Foundation
Hackathon Mode
ONLINE
Ecosystem
Tech Stack
Participants
30,000 USD
Available in Prizes
Description
Arbitrum Open House NYC — Buildathon
NYC is where startups, capital, and real-world adoption meet.
Arbitrum has infrastructure trusted by institutions and used by millions.
It’s time to connect the two.
The Open House NYC Buildathon brings three weeks of intensive building using the same tech stack that BlackRock and Robinhood bet their reputations on.
Three weeks to build something that matters.
DeFi. Gaming. Social Applications. DePin. Something entirely new?
That’s up to you.
Build with Stylus in familiar languages, or with Solidity. Deploy on Arbitrum One or a custom Orbit chain.
Bring an existing project or start from scratch.
No compromises. No limits. Just build.
And there’s plenty to play for.
The top teams will walk away with their share of a $30,000 prize pool, and an opportunity for $30k in grants in our follow-on mentorship program.
But that’s not all.
The top three teams will each win a place at the IRL Founder House in NYC in March. Four days of intense working with Arbitrum’s technical team and successful ecosystem founders.
Real mentorship, real connections, real paths from idea to funding.
We've built the infrastructure. You bring the vision.
Let's see what happens next.
FAQs
Overall prize
30,000 USD
Overall prize
Overall prize
Judging Criteria
Your project must be deployed on an Arbitrum chain to qualify. For example: Arbitrum Sepolia, Arbitrum One, Orbit chains.
Projects are assessed on the following criteria:
Smart contract quality - code following best practices, structured logically and efficiently, with minimal security vulnerabilities
Product-Market Fit - projects with clear potential to attract and retain users
Innovation and Creativity - original approaches that push boundaries
Real Problem Solving - applications that address genuine market needs
Schedule
Resource
Developer Documentation
Hey Open House NYC builders! We have compiled a list of useful information for you below. Please take a thorough look as most of the information you will be looking for will be covered here.
Faucets
Ethereum Sepolia - claim testnet ETH, then bridge it to Arbitrum Sepolia using the bridge.
https://sepoliafaucet.com/
https://arbitrum.faucet.dev/
https://www.infura.io/faucet/sepolia
https://sepolia-faucet.pk910.de/
Arbitrum Sepolia - just claim testnet ETH and you're ready to go:
https://arbitrum.faucet.dev/
https://faucet.quicknode.com/arbitrum/sepolia
https://www.l2faucet.com/arbitrum
Arbitrum Sepolia USDC Faucet:
https://faucet.circle.com/
RPC Endpoints
Useful Tools for Builders
Arbitrum Docs: https://docs.arbitrum.io/
Arbitrum SDK: https://github.com/OffchainLabs/arbitrum-sdk
Stylus Docs: https://docs.arbitrum.io/stylus
Stylus By Example: https://stylus-by-example.org
Stylus CLI: https://github.com/OffchainLabs/cargo-stylus
Stylus Rust SDK: https://github.com/OffchainLabs/stylus-sdk-rs
OpenZeppelin Rust Contracts: https://github.com/OpenZeppelin/rust-contracts-stylus
OpenZeppelin Solidity Contracts: https://github.com/OpenZeppelin/openzeppelin-contracts
Sponsors & Partners
OpenZeppelin
More sponsors coming soon!