Arbitrum Open House London: Online Buildathon

Build what's next. London 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 London 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 London in June. 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.