<div id="readability-page-1" class="page"><div><figure></figure>Arbitrum will start Open House London on May 25th. The three-week online buildathon offers a $415,000 prize pool for early-stage teams building new businesses for the programmable economy.Refer to the official tweet by ARB:<div><blockquote><div>The programmable economy needs new businesses.Open House London is helping bootstrap them with a $415K prize pool (our largest yet).Starting May 25th, early-stage teams join a 3-week online Buildathon to:- Bring ideas from concept to mainnet- Receive technical guidance viaâ€¦ pic.twitter.com/VQ0fahRZcZ</div>May 11, 2026</blockquote></div>ARB InfoArbitrum is a layer 2 scaling solution designed for the Ethereum network. Its goal is to increase the scalability of Ethereum while preserving its decentralization and security.Arbitrum operates by batching many transactions together off-chain and then submitting a single, combined proof of all these transactions to the Ethereum base layer. This greatly reduces the amount of computation and storage that the Ethereum network has to handle, allowing it to support a much higher throughput of transactions.</div></div>

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Arbitrum will launch the Open House London buildathon on May 25th, offering a $415,000 prize pool for early-stage teams developing businesses in the programmable economy. This three-week online event aims to help teams bring their ideas from concept to mainnet, with technical guidance provided throughout the process. Arbitrum is a layer 2 scaling solution for Ethereum, enhancing its scalability while maintaining decentralization and security by batching transactions off-chain.

- Arbitrum will launch Open House London on May 25th, a three-week online buildathon featuring a $415,000 prize pool for early-stage teams.  
- The event aims to foster new businesses in the programmable economy by enabling teams to take concepts to mainnet with technical guidance.  
- Arbitrum, a layer 2 scaling solution for Ethereum, enhances scalability while maintaining decentralization by batching transactions off-chain.

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Arbitrum to Start Open House London Buildathon on May 25th